The House Guest

Discovering that Katherine is free, Elena is upset. Stefan and Bonnie try to persuade Jonas and Luka to work with them, but Jonas wants Elijah alive again. He performs a ritual that puts Luka in the boarding house in invisible form. Luka tries to remove the dagger from Elijah's body, but Katherine stops him. Luka then stakes Katherine, but Damon uses a flamethrower to prevent the removal of the dagger. Luka is fatally burned, and Jonas vows to avenge him by killing Elena. Bonnie tells Elena about her relationship with Jeremy and is surprised by Elena's positive response. Jonas appears at the Grill, looking for Elena. Bonnie tries to stop him, but he disables her; Matt intervenes, but Jonas stabs him. Caroline sees Matt dying and forces him to drink her blood to save his life. Jonas attacks Elena, but she proves to be Katherine, and she bites him. Alaric tells Jenna that he loves her. Bonnie reveals that Jonas has restored her powers and told her how to kill Klaus. Caroline tells Matt that she is a vampire, but he takes the news badly. Isobel shows up at Elena's house and tells Jenna that she is Elena's mother.

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