The NCIS team investigates the death of a Navy lieutenant that died of over-hydration, which soon turns into a murder investigation. Meanwhile, Gibbs meets Ducky's new lady.

The planets of our solar system have experienced epic catastrophes throughout their long history, both raining down from outside and bubbling up from within. We'll voyage back in time to investigate the violent events that profoundly shaped the planets, including earth itself.

The sixth-round results show.

Mike feels let down when his daughters aren't into celebrating Halloween with him the way they used to. He decides that his two-year-old grandson, Boyd, can be his perfect trick or treat partner. But Kristin, Boyd's mother, adamantly tells him that she doesn't want her son to go out on Halloween.

In a special Tuesday episode the contestants are narrowed down to begin the performance round.

- For Halloween, the contestants face a crazy candy temptation and a very spooky challenge, while host Alison Sweeney and trainers Bob Harper, Anna Kournikova and Dolvett Quince get in the spirit by dressing up in Halloween costumes. First, the contestant

Kenny gets jealous of Will and Grant new found friendship. Things get worse when he finds out Grant is invited to the weekly Keen Sunday dinners. The guys try a "Star Wars" movie marathon, which Kenny is obsessed with, but Grant has never seen before.

A former Navy intelligence officer is murdered, and the agents discover his double life and a possible threat to national security.

SAMCRO discovers that they may be in over their heads with their drug-smuggling; Tara makes an important decision regarding her future with Jax.

A bad magician's Web Redemption; a collection of gross videos.

A champion equestrian is killed and potential drug use is suspected, but when Megan's daughter, who also rides, overhears details of the case, she leads the team to a clue and possibly the murderer.

Carrie and Al's investigation into the murder of a hard-partying heiress takes an unexpected turn when they discover that the woman apparently didn't exist until 18 months earlier.

The Onion News Network pays tribute to Brandon Armstrong, who was killed in a brothel fire. Shelby Cross admonishes parents not to let their children trick-or-treat on Halloween, or what she calls the "Pedophiles Christmas". The First Responders go at it over the Republican Debate.

The Final Four marksmen set their sights on the $100,000 prize and the title of Top Shot. In a series of intense challenges, one shooter attempts an unprecedented shot with the AK-47, and contestants are eliminated one by one until there are only two left standing. The final challenge pushes two marksmen to their limits and a new champion is crowned.

Mayhem ensues when Jillian becomes the boss at work.

Walter Isaacson

Zach Galifiankis, Aaron Paul, Switchfoot

The marksmen return to discuss their biggest challenges and triumphs as never-before-seen footage is revealed.

Susan Saladoff

Eddie Murphy, Jane Levy, Mayer Hawthorne

President Barack Obama

Don Rickles

The murderer has groomed schizophrenics to commit synchronised violent crimes in Malmo and Copenhagen, to highlight funding cutbacks for mental health care. Saga and Martin get a break in the case, a teenage girl who has run away from home. Could she be the witness that ultimately leads them to the murderer?

Michael is appreciative of Sian's support after a newspaper article lets it known what his salary is. He ends up confiding in her about his house being broken into, but is shocked after video footage of his fight with Wayne is emailed to him. Tom is not happy after he finds out that a teaching assistant called Greg has been brought in by Linda to assist him. Rosie tells Matt she's pregnant and ends up coming up with the idea that they draw up an agreement of what is expected.

The cloisters of Midsomer Priory are forced to open it's doors to 21st century policing after a nun is strangled to death on it's grounds. Some teenage liaisons, some missing antique silver and holy orders make it a complex investigation for Barnaby and Jones.

Kevin follows the progress made by Claire Farrow and her husband Ian Hogarth who have always dreamed of building a home big enough to have their own dance floor and DJ booth.

A town left deserted. An Angelic on the edge of desperation. A Fade on the cusp of victory. And a reluctant 17 year old boy with visions of the apocalypse - it all comes down to this final showdown. People will die. Ash will fall. It is inevitable.

The drop-in centre ends up becoming a council cut, so Rab decides to try and fight back.

JP learns that his father is suffering from some serious health issues. To try and deal with the news he decides to take his first acid trip. Oregon is upset to find out that her childhood horse is dying. After Vod has a drug overdose, she begins to question her own lifestyle and behaviour. Kingsley and Josie compete with one another to become student journalists. Josie ends up hitting a whole new low and accepts Dave's offer of marriage.