The episode opens with everyone convening at the Delphi, including Cain, who Elena is not happy to see. Of course, his idea is just to kill Savannah because that will put an end to the Undoing straight away, but Elena won't have it. Aleister is the one who must die.
Paige knows where Ruth is performing the spell so they all rush on over.
At one point, Ruth and Aleister have their mother and son moment when Ruth tries to apologize for what happened to him. It seems she really is sorry for what happened, but he thinks she is just sorry he lived.
Paige has been spelled by Aleister and tries to keep Elena from entering the catacombs. Elena makes it in, but Paige reminds her that if things go south, then Elena has to be prepared to kill Savannah to stop the Undoing.
Cain and Clay are trying to get in the catacombs, and when Clay wants to turn into a wolf to get in, Cain decides to sacrifice himself so that Clay can remain human just in case the Undoing happens so that he and Elena aren't separated in different forms forever.
When Elena reaches Savannah, in the melee she finally gets a chance to cut the tequila worm out of Savannah's arm!! No more lock and key for Aleister. So there! Elena has been stabbed, however, and when Clay arrives, they two declare their love and she dies in Clay's arms. Ruth realizes what has happened and that it's her fault. She puts her ring onto Elena's finger and brings her back to life, apparently giving her life for Elena's as she then dies.
Since Clay thinks Elena is dead, there was nothing to stop him from turning into a wolf to fight Aleister. Savannah gets her talisman back from Clara and kills her. Elena comes up and Aleister is giddy with excitement that the lone female wolf and lone male witch will fight to the death or something. Of course Elena wins and just in time for the sun to rise, so Clay can turn back into a human.
Jeremy has learned it's cool to trust in other species. Nick loves Paige and wants to be with her, but she's in charge of the coven now (of only her and Savannah?) and she has obligations and must move on.
The hour ends with another vision of Elena when she touches Savannah. She's all bloodied up and sitting alone at Stonehaven. Huh?