- "Want to figure something out? Because while Scott and Stiles were out there trying to help people from being killed, you were in here, rolling around the sheets with the actual killer. Do you get how many people she's killed? Erica and Boyd are dead, Cora is dying, and you are doing nothing! Why'd you do this to us, Derek? Was it all about the power? Were you bored? Were you lonely?"
- ―Isaac to Derek[src]
Turned into a Werewolf
Scott talks with Isaac and Stiles’s father, who is still worried about his son as Stiles has gone missing. Everyone leaves the locker room and Derek and his uncle show up. They say that they all need to have a little conversation. Scott wonders what the hell is going on. Derek says that Peter knows how to stop Jackson. Scott and Isaac tells him that Jackson’s dead. Peter says that that’s not good news because if that happened then he thinks Gerard wanted it to happen. Scott and Isaac arrive the morgue. Nobody knows what’s happening with Jackson's body. Isaac and Scott carry the body out of the hospital when they run into Allison’s father. However, Chris appears to have changed sides. He says that he doesn't believe in what his fathers doing, so he has come to help someone that he believes is doing the wright thing. Scott, Isaac, and Allison’s father pull up to a dark alleyway. Derek and Peter arrive. Derek tells them to get Jackson inside. Derek is about to kill him. Derek says that the Kanima is being controlled by Gerard and that he wanted this to happen, wanted him to get stronger. Gerard, then walks in. They all then battle it out, Allison stabs Isaac; but he’s not dead. Gerard reveals his plan to turn into a Werewolf to cure his cancer. However, he gets double crossed when Scott reveales that he exchanged his pills to pills containing mountain ash. Stiles and Lydia drive in. Lydia rushes to Jackson to show him the key they he wanted so badly. Jackson turns back into a human but gets impaled by Peter and Derek and falls to the floor. He then slowly raises off of the floor to be reborn as an Werewolf. 
- Daniel Sharman wanted to leave the show but asked Jeff Davis not to kill his character as he wished to return to the series at some point in the future.
Behind the Scenes
- Daniel Sharman who plays Isaac Lahey is British in real life.