We open in the recent past at a house in Brookline, Massachusetts, where Paige is looking after her ward, a young witch-in-waiting named Savannah. After a brief argument over whether Savannah's slowly but surely developing powers are responsible for Paige's keys suddenly moving across the kitchen counter of their own accord, the ceiling cracks, and a stranger suddenly appears at the table with Savannah.
The stranger introduces himself as Aleister and tells Savannah that she's "the most powerful witch of all." He gives her what looks like a piece of taffy, and after eating it, what looks like a worm crawls down under the skin of Savannah's arm ...
"I am The Lock," says Aleister, to which Savannah responds in a daze, "I am The Key."
Paige, meanwhile, has been kept in some sort of trance, unable to communicate with Savannah. After breaking free via a counter-spell, she is shocked to find both Aleister and Savannah have vanished.
Back in the present day at Stonehaven, Jeremy and the gang search the property for Malcolm, though the big bad wolf is nowhere to be found. Back at the house, Jeremy discovers the green ring left in the bowl of walnuts by the witches, which prompts their re-appearance. Jeremy refuses to return the ring to them, though he's forced to hand it over after Paige casts a spell that sends him floating in mid-air. Ruth puts the ring on her finger and all the doors and windows in the house that were found wide open that morning — including the gate of Malcolm's cage — suddenly slam shut.
The witches tell the werewolves that Malcolm is in their custody and they plan to hand him over to Aleister in exchange for Savannah's safe return. Jeremy offers to help them rescue Savannah … on the condition that Malcolm is then returned to The Pack. An uneasy alliance is formed, though Nick and Paige seem to have already commenced with the flirting.
Things get more tense at Stonehaven upon the arrival of a young man named Eduardo, who's looking for his Pack Alpha, Roderigo. As Jeremy invites him into the house, Clay and Elena frantically hide Roderigo's body and mop up the bloody mess on the floor. Eduardo is suspicious of "the stench of bleach" but is soon won over by Elena's charms and seems satisfied that his Alpha is not on the premises.
Meanwhile, Savannah is being held at Aleister's compound, which he claims is for her "safety." Savannah tells her host about a dream she had about a werewolf in a barn, and recalls a sign that read "Heisling Farm." Aleister seems intrigued … and pleased.
"Heisling Farm" is actually a trap set by Paige and Ruth, who are able to secretly communicate with Savannah via what Nick refers to as "Witchy FaceTime." Inside the barn of Heisling Farm, Ruth speaks to Savannah via Paige, though their "Witchy Skype Call" (another Nick term) is cut short when Savannah mentions Rachel, which prompts Logan to pry for more information and break the connection, a sudden discomfort which Paige compares to "a gin hangover."
Another witch, Bridget, delivers Malcolm to Heisling Farm and the witches and werewolves await the arrival of Aleister. When he shows up, he finds a genuinely terrified Malcolm in a chair, held by some sort of spell. Aleister causes a sharp piece of metal to fly through the air, which cuts Bridget in the stomach and breaks the enchantment, leaving Malcolm vulnerable. The werewolves rush Aleister, though they're sent flying off their feet by a dust storm he suddenly conjures … after which several of his goons arrive, ready to do battle.
As the werewolves fight Aleister's thugs (a considerable challenge, as remember these weirdos feel no pain), Aleister shares a brief exchange with Ruth, who's surprised that he knows her name. "Thanks for bringing me the wolf I need," he smirks.
Meanwhile, Nick and Paige have taken Bridget inside the barn, where she succumbs to her wounds. Soon thereafter, one of Aleister's minions enters and fights with Nick, though it's Paige who eventually overcomes her with a sleeping spell.
Elena pursues the fleeing Malcolm and the two engage in the most brutal fight on Bitten to date. Malcolm eventually gains the upperhand and proceeds to strangle the life out of Elena, though he's ultimately undone when she slashes his neck open with her super-sharp nails. As Malcolm dies, his last words to her are: "Run."
A surprised and impressed Aleister approaches Elena, claiming "Malcolm wasn't the strongest after all." Elena rushes Aleister, though he calmly outstretches his hand and we slam to darkness. Uh-oh ...
Back at the farm, Aleister's goons are loading their dead into one of their trucks, which inspires Logan to pretend to be a corpse and hitch a ride to where he hopes will be wherever Rachel is being held.
As the sun sets, Jeremy and Clay discover Malcolm's body … though Elena is nowhere to be found.
The next morning at Stonehaven, Nick watches as Paige performs a burial ritual for Bridget, and Clay interrogates their prisoner, the young woman who fought Nick in the barn, as to the location of Elena, Logan and Savannah. The woman is dazed and incoherent, repeating the phrases "The key that unlocks us to The Great Undoing" and "Four Six," until she finally stabs herself in the stomach. Whoa!
The episode ends with Elena strapped to a gurney in some unknown location, screaming as she tries to escape from her bonds. Now three people need rescuing!