"Plan B" is the 6th episode of the second season of The CW television series, The Vampire Diaries and the 28th episode of the series overall. It originally aired on October 21, 2010. The episode was written by Elizabeth Craft and Sarah Fain and directed by John Behring. Plot The episode starts with the scenes switching between Elena (Nina Dobrev) with Stefan (Paul Wesley) and Katherine with Mason (Taylor Kinney) waking up together. Elena and Stefan talk about how to keep hiding from Katherine and she keeps feeding Stefan with her blood, meanwhile Katherine tries to make Mason tell her where he hid the moonstone, however he tells her that it is safe and that he will give it to her later that night. Jeremy (Steven R. McQueen) pays a visit to Damon (Ian Somerhalder) because he wants to help, as he says, and tells Damon what he has learnt about werewolves from Tyler (Michael Trevino) and that Mason is looking for a moonstone. Alaric (Matt Davis) arrives with more information from Isobel's research that says that moonstones can be used to seal a curse and they wonder if Mason wants it so he can reverse the werewolf curse. Everyone is at the preparations for the Masquerade Ball and Elena gets the chance to fill Bonnie (Kat Graham) in on everything around Katherine and what she was doing all this time with Caroline (Candice Accola) and her fake fights with Stefan. Meanwhile, Mason looks surprised to see Stefan alive and he asks him what they did to Sheriff Forbes (Marguerite MacIntyre). Stefan reassures him that Liz is fine and Mason leaves. While walking away, Mason bumps into Bonnie who gets a vision of him and "Elena". She tells Stefan about it and he figures out that Bonnie did not see Elena kissing Mason but Katherine. Stefan informs Damon about the connection between Mason and Katherine and they are sure that Katherine is using him for something and they need to find out what. Jeremy offers his help and says that he can take the moonstone from Tyler, but Tyler gave the moonstone to Mason because he doesn't want to have anything to do with curses and supernatural anymore. Stefan and Damon ask for Bonnie's help so they can "kidnap" Mason and make him tell them Katherine's plan and where the moonstone is. Even though at first Bonnie does not want