When Lydia goes missing from the hospital, werewolves and hunters alike begin a search to discover not only where she is, but what she's become. (MTV)

The night before the new full moon, Isaac's father is murdered. When he's taken into custody, Scott, Stiles and Derek resolve to break him out before the Argents get to him first -- and before the newly bitten teen turns into a werewolf. (MTV)

Scott struggles to stop Derek from creating new werewolves, while Argent decides to officially begin Allison's training and the new creature in town takes another victim. (MTV)

When the new shapeshifter strikes again, Scott has to recruit a reluctant Allison to acquire a rare book in Gerard's collection, while also once again surviving dinner with her family. (MTV)

Derek becomes convinced that Lydia is the shape-shifter, and forces Scott to help him protect her. (TV Guide)

With startling new information about the shapeshifter, Scott and Stiles hurry to protect their friends while Allison is given an investigative task by her family. (MTV)

As Lydia begins to make connections about the bite from Peter, Jackson causes new problems for Scott and Stiles while Derek has a crisis of faith in his leadership as a new Alpha. (MTV)

During a secret concert, Scott and Stiles come up with a method to trap the new shapeshifter. At the same time, Allison's mother comes up with a plan of her own to take care of Scott once and for all. (MTV)

Even as his relationship with Allison becomes further strained, Scott and Stiles must attend Lydia's birthday party while Derek locks his new wolves up to watch after them on their first full moon together. (MTV)

Allison tracks Derek to the sheriff's station, where Scott, Stiles, Melissa and Sheriff Stilinski are being held hostage. (TV Guide)

Scott plays in the championship lacrosse game and must also figure out a way to stop Gerard. Meanwhile, Allison continues her hunt for Derek and his wolves. (TV Guide)

Scott races to uncover Gerard's master plan following a shocking death on the lacrosse field. Meanwhile, Derek plots to take Gerard down using his own methods. (TV Guide)