On the 4th season premier, TAPS investigates a garrison used during the Revolutionary and Civil Wars, in Philadelphia's Fort Mifflin. Of which claims have been made by visitors and facilitators of the historic site.

(Case #1: Mount Holly, New Jersey - Burlington County Prison)
The TAPS team goes to investigates a Prison Museum called the 'Burlington County Prison Museum', which is a historical jail in Mount Holly in New Jersey; after Dave Tango's father, an ex-police officer & armature ghost hunter, had a paranormal experience in this museum.

(Case #2: Norwich, Connecticut - McArthur's House)
Later TAPS, on there second investigations of the episode, goes to investigates a Northwich, Connecticut home of which their has been claims of people hearing disembodied voices and objects that move of their own accord, which are terrorizing a young girl.

(Case #1: Belchertown, Massachusetts - Clapp Memorial Library)
TAPS investigates strange occurrences happening to Clapp Memorial Library in Belchertown, Massachusetts. Where the local night custodian claim to have heard unusual noises and believes the first librarian till haunts this Library.

(Case #2: Bristol County, Massachusetts - Attleboro House)
Later TAPS, on there second case of the episode, heads over to a house in Attleboro, Massachusetts to investigate claims concerning a family in a 300 year old duplex renovated house reportedly haunted over four generations.

The TAPS team goes to Gettysburg, Pennsylvania where an ex-military headquarters during the Civil War that was converted to a local bed-and-breakfast called the "Cashtown Inn" has been reportedly haunted by apparitions of moving objects, ghostly soldiers, disembodied voices and other paranormal phenomena.

(Case #1: Norton, Massachusetts - Medeiros' House)
TAPS heads over to a Massachusetts household residence where a family is reportedly plagued by shadowy figures, phantom footsteps and other paranormal activities.

(Case #2: Trinway, Ohio - Prospect Place)
Later, on the second investigation of the episode, TAPS heads over to Trinway, Ohio to investigate Prospect Place which was a stop along the Underground Railroad back in 1860's during the America Civil War. Also, It's the site of many paranormal activities which include: phantom scents and spectral whispers.

The TAPS teams goes on to investigate three buildings at the Wright-Patterson Air Force Base in Dayton, Ohio. (Arnold House, Building 70, and a Warehouse located inside Building 70)

(Site#1: Near Dayton, Ohio ~ Wright-Patterson Air Force Base - Arnold House)
First off TAPS investigates the Arnold House, which is the site of a formal residential house built in 1841 that was bought by the Air Force. Where reportedly ghostly children still roam the house, phantom footsteps and objects moving be themselves.

(Site#2: Near Dayton, Ohio. ~ Wright-Patterson Air Force Base - Building 70)
Later TAPS heads on to investigate Building 70, which is a building that was built during the second world war. This building also contains a office space and a warehouse. The locations of which there has been claims concerning phantom typists, an elevator with a mind of its own, disembodied children's laughter, and phantom apparitions.

(Case #1: Bretton Woods, New Hampshire - Mount Washington Hotel)
The TAPS team heads over to New Hampshire's Mount Washington Resort where TAPS investigates claims that the staff of the resort have encountered things such as strange cold spots and other possible paranormal activities. Also in this resort, it has been rumored that the spirit of a deceased princess roams around.

(Case #2: Providence, Rhode Island - Ruffstone Tavern)
Later, on the second investigation of the episode, TAPS heads over to the Ruffstone Tavern in North Providence, Rhode Island, where there have been claims of paranormal activities concerning this place such as strange odors, and feelings of being watched.

TAPS heads over to Nevada to investigate two separate locations both well known for being plagued by Paranormal activities".The Goldfield Hotel" and "The Old Washoe Club"

(Case #1: Goldfield, Nevada - Goldfield Hotel)
First, TAPS heads over to the the Goldfield Hotel located in Goldfield, Nevada where this 100 year hotel that is about the be renovated, has been reportedly plagued by numerous hauntings and paranormal activities that include phantom shadows and disembodied voices.

(Case #2: Virginia City, Nevada - Old Washoe Club)
On the second investigation, TAPS heads over to a former millionaires club that was built in 1862 and is now a bar know as the "Old Washoe Club". Patrons as well as employees and former employees have reportedly experienced several paranormal activities such as disdained heads floating around, ghostly children standing hauntingly gazing, and many other things.

The TAPS team heads over to a former psychiatric hospital in Weston, West Virginia that was constructed near the beginning of the civil war in the 1850s. Known as the "Weston State Hospital" formally known as the "Trans-Allegheny Lunatic Asylum", TAPS will investigate claims made by the owner, tour guides and volunteers of the asylum concerning paranormal activities. Witnesses have claimed to of seen and heard ghostly entities/phantomly figures, disembodies voices, phantom black blobs of smoke, and tugging of their clothes.
Newly renovation progress has commenced in this hospital leading to newer claims that have been brought to TAPS by the renovation team to investigate.

(Case #1: New Haven County, Connecticut - New Haven House)
TAPS heads over to a New England home in New Haven County, Connecticut where they investigate claims made by the family regarding paranormal activity. The house itself has a long history associated with it. It is located on land once believed to be a site where Native Americans use to live on, American revolutionary war battle grounds, and also currently has greenhouses all over the property and still have working land for farming purposes.

(Case #2: Manchester, New Hampshire - Palace Theater)
Later, on the second investigation of the episode, TAPS heads to investigate a former vaudeville in Manchester, New Hampshire known as Palace Theater. Paranormal claims include a man committing sleeping and returning to haunt the place, strange voices and noise, apparitions, shadows, and phantom footsteps. Jason is concerned because it is a theater and noises and voices could be the product of the architecture for such a place.

(Case #1: Cape Cod, Massachusetts - Colonial House Inn)
The TAPS team investigates the historic Colonial House Inn located in Cape Cod, Massachusetts. Built in 1730 by a sea captain named Josiah Ryder, this inn has been reportedly plagued by paranormal activities such as people reportedly hearing a crying man & children's laughter where there are none, shadowy figures, ghostly figures of an elderly woman & man, and also feelings of paranoia .

(Case #2: Moss Beach, California - Moss Beach Distillery)
Later, on the second investigation of the episode, TAPS travels to Moss Beach, California to investigate inside a Distillery known as Moss Beach Distillery. According legend, the distillery is haunted by a ghost of an old woman known as the "Blue Lady". Eyewitness have reported that objects have move by themselves and accredits this to Blue Lady after other witness have seen her apparition roaming inside the distillery.

TAPS heads over to Dave Tango's home state of New Jersey to investigate two separate locations, both well known for being plagued by Paranormal activities. Dave Tango's father, William "Bruce" Tango, tags along for the two investigations. The "Red Mill" and "Proprietary House" are investigated.

(Case #1: Clinton, New Jersey - The Red Mill)
TAPS heads over to Clinton, New Jersey to investigate a 19th-century mill, known as the Red Mill. The Red Mill Museum Village is over 200 years old, and has been used for making such products as wool, talcum, and grains. Paranormal claims include phantom footsteps, machinery stopping and turning on by themselves, strange noises like the clicks from a typewriters where none are present. People complaining about something touching them but nothing being visibly present, ghostly apparitions and other unexplainable noises & voices.

(Case #2: Clinton, New Jersey - Proprietary House)
On the second investigation, the TAPS team heads over to Clinton, New Jersey where they will be checking out the Proprietary House. Proprietary House was the home of the state's last royally appointed governor. The Proprietary House was once the house where Ben Franklin's illegitimate son,William Franklin, lived in. Paranormal claims associated with the mansion include ghostly apparitions of a little boy in colonial clothes, and a woman in white have been reported. Strange beams of light coming off the walls, phantom footsteps & shadow figures and unexplainable noises & voices have also been reported.

On the mid season finale, TAPS heads to Pea Patch Island, Delaware where they will investigate a formal POW camp during civil war known as Fort Delaware. Fort Delaware is the site of one of the largest civil war prisons. This island fortress, which is only accessible by boat, was built in 1848 and took 20 years to build. It was originally built as an artillery defense camp for the Union and was turned into a POW camp during civil war. It housed over 33000 prisoners, and over 2500 people had died at this fort.

Three major claims have been brought to the attention of TAPS, all three include physical apparitions of "cleaning lady", a "female cook", and a "soldier". The cleaning lady was claimed to have been seen inside a room and cleans a kettle then disappears. The female cook was claimed to have been seen inside the kitchen area lifting pots and smiles back at eyewitness then disappears, it was reported that the same apparition had been heard laughing and causing doors to become locked. The Civil war soldier had been spotted throughout the fort. Other claims include phantom whispers & voices, a lamp thrown at people without reason or cause.

TAPS is joined by guest investigator, and "Hunt for a Hunter" winner, Mark Fusetti.

On the mid season premier, TAPS heads over to Iron Island, Buffalo, New York where they'll be investigating the Iron Island Museum. The Iron Island Museum was a formal Episcopal Church built in 1883 and later reworked as a funeral home/parlor in the 1950's. In the year 2000 it was renovated to be the city's museum. During renovation works, renovation workers had found more then 32 boxes of human ashes and remains. During the building's life as a funeral home, there was a person who past away during a wake. Volunteers for the museum are afraid to even go inside of it. Paranormal claims and activities include ominous shadow figures, cold spots, objects moving and falling by themselves, feeling of being followed, doors that are locked becoming unlocked and open by themselves, full body apparitions, and appearance of small children where none are present at the time.

(Case #1: Pawtucket, Rhode Island - Slater Mill)
TAPS heads over to visits the historic Pawtucket Slater Mill, which is the oldest industrial site in the US, and is a state landmark. The mill is also the first successful water powered factory in the United States. The mill was opened in 1793 with initially 9 children working on the machinery (7 girls and 2 boys). These children where hired to work on the machines small and tight areas surrounding the machinery. Some of the children lost their lives be accidentally getting ought up the machinery while it was still running, while other children had lost fingers and other appendages while working on the machinery.

Claims of paranormal activity include: Rumored to have the spirit of a 9 year boy roaming the mill, several cold spots in different locations, the feeling and sensation of watched inside the bell tower of the mill and general feeling of discomfort, noises indicating the mill being operated, old mill machines turning on be themselves with no one operating them, alarm systems not functioning stating that it was due to people still inside the mill when there are none, a mill wheel turning around by itself without cause and on it's own.

(Case #2: Simsbury, Connecticut - Pettibone Tavern)
On the second case of the episode, TAPS heads over to Simsbury, Connecticut to visit the Pettibone Tavern.
The tavern was built in 1780 where a sea Captain named Jacob Pettibone use to live in. The tavern recently underwent a damaging fire. The tavern's owners invited TAPS to investigate before renovation work takes place. It is rumored through legend that Captain Pettibone's daughter, Abagael, was beheaded along side a man that wasn't her husband, by her husband after he had found them sleeping together one day.

Claims of paranormal activity include:Rumored to have the spirit of Abagael roaming the tavern, other full body apparitions which include a dark man standing in a corner, hearing one's own names being called out, strange images inside a bathroom mirror which use to be Abagael's room, sensations of people touching their shoulders, phantom smells of barnyard-like kinds of odors.

(Case #1: North Kingstown, Rhode Island - Carriage Inn)
TAPS heads over to North Kingstown, Rhode Island to investigate the "[Hoof, Fin, and Feathers] Carriage Inn" banquet hall, where they will look into claims made by employees of this former inn and brothel which was built in 1760. Claims include: Voices of dead children and general disembodied voice, specifically a little boy who, according to legend, is "proclaiming the innocence of his father who was hung in the attic" of the Inn; full body apparitions spectral sightings, phantom appearances of a woman dressed in 1700's (or possibly 1800's) clothing, apparitions of a little girl that has burn scars over her face who stands still and only stares outside; apparitions of dead prostitutes roaming inside he Inn's barn, unknown forces apparently slapping and grabbing the Inn's employees, whispers, and some cold spots in the attic of this banquet hall.

(Case #2: Groton, Connecticut - Stiteler House)
Also, the TAPS teams heads to Groton, Connecticut to investigate a residential house (a private home) claimed to be haunted. The Stiteler family, a self proclaimed 'military family', have all experiences and seen an apparitions of something apparently looking like a child, a boy, with the physical characteristics of having black nose, black hair, black eyes, black mouth and squiggly arms. Inside he room of their youngest child they have seen toys turning on my themselves a he same time every night (at 3:00AM.). Including a rocking-battery-powered-toy-horse turning on by itself without any batteries inside of it, and a TV set turning on by itself.

TAPS heads over to Buffalo, New York, to investigate an old train station known as the Buffalo Central Terminal. The terminal was built in 1929 and began running on the same year. It was operation for about 50 years when it closed in 1979. In the station's prime, the station would have at least 200 trains passing by the station in an average day. The terminal was used in World War II to transport several American troops, as well as German POWs. The station's main office tower is 14 stories high, and the length of the entire complex is over 500 square feet. After the terminal was closed, there were a few private investors bought the station, notably Tony Fedele, who bought the station in 1979, to which this investment on the station was claimed to be his "demise". In later years after Fedele left he project, the station went abandoned for several years, and had been vandalized greatly, causing hazards to people who go inside the station. The station is currently undergoing through an extensive renovation and restoration work, the which is claimed to be the reason of the recent spike in paranormal activity in the station.

Claims of paranormal activity include: Residual type hauntings like witnesses claiming to have seen two ghostly apparitions in the third floor standing by a water fountain, and when these witnesses went near these apparitions, the apparitions vanished, including the water fountain they were drinking off of. There have also been claims that the spirit of Tony Fedele, former formal owner of the terminal who tried to renovate and save the the satiation but failed, still haunts this terminal; Tony's demise is blamed on his passion to renovate the Terminal. A female apparition is reported to haunt the mail room . Also, it is claimed that a German speaking ghost haunts the lower levels of the terminal. And several other types of haunting (both residual and intelligent) and strange apparitions are also reported. Other claims include: Cold spots, extreme feelings of dread, strange noises and voices, and feelings of being watched.

TAPS heads over to Florida to investigate two separate locations. First, TAPS heads to the 'Seven Sisters Inn' located in Ocala, Florida. Where they they will investigate claims made by employees and guests from this Inn. Later, TAPS heads to the 'Renaissance Vinoy Resort' located in Saint Petersburg, Florida, where they will also investigate other claims of paranormal activity.

(Case #1: Ocala, Florida - Seven Sisters Inn)
On the first investigation, TAPS heads to Ocala, Florida to visit the Seven Sisters Inn. In which they will investigate two different 'Victorian' style buildings located at the inn at the same night. The first building is known as the "Pink House", the second building is known as the "Purple House". Both buildings where built in the 1880's while only the Pink House was the original Seven Sisters Inn and was built in1888 by the Scott family. Both of the inn's houses was built over the former location of the battle field of the "Seminole Indian War", and was used as a triage camp as a part of the old Battle of Fort King. During the war, it was said many had died over the territories of these houses. In earlier years, the inn used o be a boarding house for the elderly. And inside the Pink House, it is said an elderly woman had died inside the in at some time in the past. The Purple House Is the third building to be built at this property. The first building was burnt in a fire. And at the same time, the building next door had also caught fire. The Purple house was built on it's place.

Claims of paranormal activities include: It has been mentioned that both houses have diffren charecterisics to them. The Pink House has a more light and happy side to it, while the Purple House has a more darker side to it. Inside the Purple House it is claimed that the apparitions of many men, woman, and children still reside inside the house. Claims made by guests and employees of an apparition of a man sitting in a specific chair inside one of he rooms of the Inn smoking a cigar, and later disappearing. This same apparition is also claimed to have thrown the chair he was sitting on at employees. The apparitions of small black phantom shadows, and other shadowy figures (aka, shadow people) that look like dogs. Inside the Pink House witnesses claim to have moved books and then witnessing these books moving by themselves back into the their original positions, An employee almost falling on stairs, but was saved by some sort of entity that pulled her back up so that she wouldn't fall. The form or appearance of a tall lady dressed in white who walks amongst a doorway and grabs objects and smashes them. It is said that this lady does not like fire because of other claims of candles mysteriously lighting off by themselves. A mysterious man with a deep voice has been claimed to utter "get out" to guests at the inn. Inside both houses it has been claimed that it could be both an intelligent and/or residual kind of haunt. Both houses have claims of phantom footsteps, mysterious moans and sensations.

(Case #2: St. Petersburg, Florida - Renaissance Vinoy Resort)
On the second case of the episode, TAPS heads over to St. Petersburg, Florida to visit the Renaissance Vinoy Resort, where TAPS will spend the night in and investigate all sorts of claims of paranormal activities. The Renaissance Vinoy Resort was built in 1925 and has 360 rooms in it. The resort has been visited by numerous figures of the past, like Jimmy Stewart and Merilyn Monroe. The resort is also frequently visited by baseball teams heading over to play against the Tampa Bay Devil Rays. The baseball players are said to have the most frequented paranormal experiences inside the resort.

Claims of paranormal activities include: Employees claiming to have heard eerie footsteps inside the ballroom area of people walking around in a wooden floor, but he room in question is carpeted. A mysterious apparition of a lady in white and a man wearing periodic clothing roaming the hotel's fifth floor.

TAPS heads over to Saint James County, Vacherie, Louisiana to investigate the infamous Oak Alley Plantation Restaurant & Inn. The plantation was built in 1839 and took two years complete. It was built y slave laborers, to which the plantation had. The plantation's walls are said to be 16 inches thick of solid brick. The plantation was used in the movie "Interview with a Vampire", and is now used as a museum for historical tours and also as a restaurant & inn.

Claims of paranormal activity include: A ghost that the employees call the Lady our House, who is a black vision of a mass who roams a staircase. (Theories point to that the this woman could be the first female owner of the plantation, named 'Selena'). This same apparition has also sometimes been seen through mirrors, but not directly looked at. Selena was also spotted on several other rooms including a bedroom where she has been spotted laying on a bed. Another apparition of a shadowy woman figure wearing an "antebellum" costume has also been reported. The phantom apparition of other formal owners and residents of the plantain. Objects falling and moving by themselves, like a candle that were resting on top of a candelabra falling off the candelabra and unto a table, then when put back to the candelabra, the candle would throw itself towards a door. An attic room where feelings of dread usually kick in when individuals enter it. Other shadow figures, other objects moving by themselves, feelings of being touched without a source, strange noises voices and sounds of people crying where there are none, empty chairs rocking and creaking by themselves.

TAPS is joined by Ghost Hunters International investigator Barry Fitzgerald.

TAPS heads over to an "ancestral home" located in Dayville, Connecticut, where claims of paranormal activities involving a malevolent spirit is probed. TAPS then heads to Appleton, New York to investigate a local winery.

TAPS heads to Massachusetts to investigate two separate locations. One located in Springfield, the other in Leominster.

TAPS heads to San Francisco, California to investigate the US Navy aircraft carrier the "USS Hornet" CV-12. TAPS is joined by "Eureka" star Colin Ferguson who will assist TAPS on the investigation.

TAPS showcases their findings and results regarding the investigation that took place live on Halloween in Fort Delaware located in Pea Patch Island.

Josh Gates sits down with TAPS members in a look back at TAPS' previous investigations of the last seasons of the show. As well as a special look back at the Ghost Hunters first episode, including never before seen footage of the investigation.

TAPS explores the Clovis Avenue Sanitarium, a sixty-six year-old, 8,000 square foot mansion. The former sanitarium opened in 1942, and stayed in service up through 1992. In that time, countless patients passed through the halls, and thousands died there.

TAPS heads over to San Diego to investigate an old 1898 steamboat ferry named the "Berkeley". TAPS also investigates the oldest active ship in the world, the Star of India.

Ghost Hunters' season four finale takes the TAPS team to Portsmouth Harbor Lighthouse and Fort Constitution in New Castle, NH. The 48-foot cast-iron tower was erected in 1771, with the grounds covering approximately 2 acres including Fort Constitution and the Keeper's Quarters. After years of late night reports from the Coast Guard and other witness accounts, the members of the Friends of The Portsmouth Lighthouse want to know if the lighthouse and surrounding grounds are truly haunted. Jason and Grant will be facing one of their most interesting challenges as they explore the Portsmouth Harbor Lighthouse, the Fort Constitution and the Keeper's Quarters.