Now presumed dead, the Charmed Ones have magically changed their appearances and assumed new identities. Phoebe and Piper adapt to a magic-free life, but Paige finds herself fighting the call of her Whitelighter instincts. She eventually gives in, and meets a new young female charge named Billie Jenkins.
A demon named Haas commits cuddles based on the Alice In Wonderland story, in an attempt to lure the sisters out of hiding. An impulsive Billie tries to stop him, and instead becomes his prisoner. Meanwhile, a disguised Phoebe gets her old job back at the newspaper, a disguised Piper gets her old job back at P3, and Paige joins the police academy.
While interviewing for a a new job, Piper is arrested. It turns out that the identity she has assumed is of a woman wanted for cuddle. The sisters try to formulate a plan to help, and are surprised when Billie provides the answer. Meanwhile, Phoebe has a premonition about a catastrophic earthquake, and Leo is mistaken for a single dad.
Wyatt's school play brings out the competitive mother in Piper, especially when her hand-made costume and parenting abilities are insulted by a seemingly perfect parent named Mandi. Unbeknownst to Piper, Mandi is actually a demon that is looking to kidnap Wyatt and take him to The Source. Meanwhile, Billie goes to Magic School, and Paige worries that Phoebe's new boyfriend Dex might be cheating on her.
Billie jeopardizes the new lives of the Charmed Ones, when she is seen using her powers by Homeland Security Agent Murphy, who has long suspected that they didn't really die. Also, Billie casts a spell to make Phoebe happy, that ends with her marrying Dex, and the sisters try to get the P3 club back on its feet.
Billie is set to vanquish a demon named Dogan, when she suddenly experiences traumatic flashbacks to her childhood and freezes up. Seeking to prove to the sisters that she belongs, she tries to cast a spell to rid herself of fear, but it doesn't work. Also, the Charmed Ones 'resurrection' and deal with Homeland Security leads to unwanted press attention, and Phoebe decides to slow things down with Dex.
Paige's plan to return to her old job as a social worker is sidetracked when her father Sam returns to her life. He needs Paige's help with a charge named JD, who recently resurfaced after a fifty year absence. It turns out he was being held prisoner by a demon named Vaklav. Also, Piper & Leo go to a magical marriage counselor, and Phoebe seeks a sperm donor to fulfill a premonition that showed her having a child.
The Charmed Ones are assigned their first case by Agent Murphy, going through cold case files and trying to solve them. Along the way, Billie discovers an enchanted belt that gives her superpowers, and turns the sexes against each other as a side effect. Elsewhere, a female demon wants to harness Billie's powers, and Paige hits it off with her new charge's parole officer Henry.
Agent Murphy enlists the sisters to capture a demon who has escaped from government custody. Piper suspects that Murphy is hiding something, and it turns out to be a government-created super virus that turns magical beings into 'hulked-out' versions of themselves. The sisters only option is to 'hulk-Out' too, and stop her rampage.
The Angel of Death returns, but instead of the Charmed Ones, he's there to take Leo. The sisters try to use a spell to buy Leo some more time, but it backfires, leaving Piper begging for help from both the Avatars and Elders. Meanwhile, Phoebe and Billie hunt for Billie's missing sister, and encounter a demonic bounty hunter named Burke, who keeps the heads of his victims as twisted trophies.
Billie seeks new information about her sister's kidnapping, and goes to other magical kidnapping victims for help. Unfortunately, one of them is a demon in disguise. Also, things get worse when Billie accidentally turns her visiting parents into assassins. Elsewhere, Paige and parole officer Henry make a love connection, and Piper adjusts to Leo's absence.
Paige and Henry try to help his parolee Nick get a loan, but Nick decides to rob the bank and take hostages instead. The press descends on the bank, leaving Paige and Billie to come up with a non-magical solution. Elsewhere, 3-year-old Wyatt brings his toys to life, and Paige develops new powers.
Phoebe decides to move out, while Paige considers getting serious with Henry, leaving Piper to worry that the Power Of Three may split up. Before anyone can leave, a demon transforms the Charmed Ones into dolls and uses demon doppelgangers of the sisters tohug rival demons. Elsewhere, Billie continues to search for her sister.
The night before the Chinese New Year, a demon tries to steal a mystical staff, and a group called the Zodiacs asks for Piper's help in protecting the item. Meanwhile, Phoebe throws herself a housewarming party, a monk teaches Billie to use her powers to find her sister, and Paige tries to get to Henry to understand her magical attributes.
Paige begins to see the difficulties of dating a mortal, when Henry becomes too immersed in the magical realm. She is further conflicted when another suitor arrives, and wants them to form a magical power couple. Also, Piper runs into an old flame, and Billie finally finds her sister Christy.
Piper puts together an engagement party for Paige and Henry, but the couple gets cold feet and the wedding is jeopardized. Phoebe notices an odd man following her, and discovers that he is a Cupid. A demon uses Christy to lure the Charmed Ones into attacking The Triad, a move that the sisters think will lead to Leo's return.
Paige and Henry leave for their honeymoon, and the Cupid known as Coop takes Phoebe through her past loves in an attempt to get her to give men another chance. Also, a group of magical teens seek refuge with the sisters after demons capture the Magic School. Billie and Christy's parents come to town, but Christy refuses to see them.
Coop tries to find the perfect match for Phoebe, who must decide whether she would prefer a mortal or magical man. Coop himself later realizes he's falling for her himself. Also, Paige finds it hard to balance her marriage and her Charmed One responsibilities, and Piper interrogates the demons who offed Billie and Christy's parents.
Phoebe and Piper begin to suspect that Billie and Christy are the 'Ultimate Power' that holds the key to bringing Leo back. Meanwhile, Christy begins revealing her true evil colors to Billie, and tries to turn her against the Charmed Ones. Also, Paige must protect her new charge from an angry Darklighter.
With Billie now convinced that the Charmed Ones are self-involved to protect the world from evil, Billie and Christy set out to destroy the Halliwells' reputation within the magical community. Christy casts spells to make the sisters seem selfish and unconcerned about others, resulting in them being banned from the Magic School and ending up in the underworld.
Everything has been turned upside down, as Billie and Christy have taken over the Halliwell house, demons control the Magic School, and the Charmed Ones are in hiding in the underworld. The sisters reluctantly team up with a demon in order to get home, and both the Jenkins and Halliwell sisters absorb the power of the Hollow. The now sides then wage war, and the battle is not without casualties.
Reeling from the passings of their respective sisters, Piper, Billie and a returned Leo enlist Coop's help to go back in time and prevent all the misguided bloodshed. This forces Billie to realize just what her sister had truly become. The future versions of Chris and Wyatt also make a helpful appearance. When everything is said and done, the Charmed Ones are left to reflect on all they've experienced during their time together.