One year ago, Aleister lures an attractive young woman into a basement decorated like a witch's secret sex den. He strips her, handcuffs her to the bed and takes out the HandyCam … though it isn't until Clara enters that she starts having second thoughts about all this. "This one's perfect … I want her!" hisses Clara, and the poor girl starts to freak out as the former witch lies down next to her, the camcorder capturing whatever unpleasant thing is about to happen next …
Back in the present day at Stonehaven, Jeremy is patching up Clay, who's still recovering from being possessed by Aleister. Ruth, who admits she's surprised that Clay survived the ordeal, tells them they must find Clara, as Aleister mentioned "a great woman " who taught him. As The Undoing is in full swing, they must kill Aleister by sunrise or all witches worldwide will be dead.
Meanwhile, Logan visits Rachel at her parents' house, where she doesn't invite him in and claims she needs time and space to process the madness of the past few weeks. She also tells Logan that she got an abortion … no more werewolf baby. Logan is heartbroken as Rachel retreats back into the house.
As for Savannah, she's once again Aleister's prisoner, and Clara has her talisman. Clara feeds her some B.S. about how the other witches just want to control her, but Savannah's heard that song and dance before. Clara doesn't like her attitude, though Aleister is more concerned about the werewolves, preparing a new Goon Army to deal with them.
Jeremy encourages Ruth to strike back against Aleister using his own nasty left-hand magic. Ruth retrieves a strand of Aleister's hair from the storage shack and casts a spell that makes him cry out in extreme pain. Using Savannah to contact Ruth, Aleister swears revenge against her and every witch … after which Jeremy starts to convulse and change into a wolf, seemingly through no control of his own. What's going on? More dark magic?
After teaching a drunken lout some manners outside a bar, Logan gets the attention of an underground fight club promoter, who invites him to participate in a match that night. Needing to let off some steam, Logan accepts … and finds that his opponent is none other than Zachary Cain, who's still a little pissed off that Clay castrated him back in Season One. As they fight, Cain too starts to suddenly change into wolf form, though Logan chokes him out before he can make a scene.
Jeremy and Cain can't control their transformations, Clay's head wound won't heal … what gives? Ruth has the answer: The Undoing also involves the werewolf curse being lifted, which means come morning, they better not be in wolf form or else they'll stay that way forever. Sheesh, nothing is easy.
Meanwhile, Elena, Clay, Nick and Paige have infiltrated Clara's house, where Nick finds the staircase leading into Aleister's evil sex den. They find the video camera and watch in horror at the witchy snuff film featuring Clara possessing Aleister's would-be one-night-stand, after which Clara returns to her own body and Aleister suffocates the girl. Elena discerns that this was a test run for Clara's master plan: she wants to possess Savannah, and therefore get her witch powers back.
Logan visits Cain and tells him about the werewolf curse being lifted, encouraging him to join the Pack to help strike back against Aleister. Logan is shocked to find Amber, Cain's would-be Werewolf Queen, brain dead and on life support, still stuck in mid-transformation. After Logan receives a frantic phone call from Rachel, who claims there's "something wrong with the baby" (there was no abortion, thank God), a heartbroken Cain says goodbye to his ladylove and pulls the plug.
Back at Clara's happy house of joy, Elena and Clay have gone upstairs, after which Nick and Paige suddenly find themselves trapped in the basement. Where there was once a door is now a solid wall, which Paige says is a "witch's door" (natch) controlled by a trigger. As they search the room for something that might be the trigger, Paige collapses in pain as The Undoing delivers another punch to the gut.
As Paige drifts in and out of consciousness, Nick proclaims his love for her. "You see beyond the jokes and the bravado," he says, to which Paige weakly adds, "And the hair." Nick swears he's not going to let her die, after which he finds the trigger and opens the witch's door, revealing Clay and Elena, who had made short work of an invading gang of Aleister Goons.
Back at Stonehaven, Ruth claims that in order for her to properly wield all this dark magic being used to fight Aleister, she must harness the power of all the coven leaders before her at a place called The Catacombs, the witches' sanctuary since the 1700s. As The Catacombs are in Boston, Ruth hits the road as Logan arrives with Rachel, who's screaming in pain due to the werewolf curse being lifted on her unborn child. Jeremy tends to her as best he can, though he's heartbroken when Logan expresses his joy at the curse being lifted — now he, Rachel and their son can live a normal life!
An enraged Aleister arrives at Stonehaven, demanding Jeremy hand over Ruth. As he works his dark magic to make Jeremy writhe in pain, he's suddenly attacked by Logan in wolf form. Aleister impales his attacker with a pair of antlers and flees, after which Logan transforms back into human form and dies in Rachel's arms. LOGAN!!
A heartbroken Jeremy calls Elena and Clay and tells them to get to Boston to protect Ruth, keeping the news of Logan's death to himself for now. As he prepares to leave himself, he gets an unexpected visitor: Zachary Cain, who wants to join the Pack. "Witches, zombies, dragons, whatever - Jeremy, you just point me in the direction of what needs killing." Yes!
Ruth has indeed arrived at The Catacombs and has been letting Aleister have it, causing gruesome bruises to appear on his face and forcing him to vomit black bile. Clara knows where Ruth has gone, and she, Aleister and Savannah arrive in Boston, facing the sleek modern building under which is the ancient witches' sanctuary. "Let's finish this," growls Aleister, making a meta-reference to the fact that Season 2 has only one more episode!