Pack MentalityTeen Wolf : Season 1 Episode 3 \/\/FREE\\\\
Completely stunned by this answer, Scott realizes that there is another Werewolf in town, which Derek confirms. Derek goes on to explain that he and Scott are Beta werewolves, but that the werewolf who bit Scott was an Alpha, the most powerful, dangerous, and animalistic of their kind. He then admits that his sister Laura came to Beacon Hills to seek out the Alpha, and that now he's doing the same, but he doesn't think he can do it without Scott's help. Scott doesn't understand why Derek needs him, so Derek informs him that since the Alpha is the one who bit him, he's part of the Alpha's pack, which makes him the one that the Alpha wants.
Pack MentalityTeen Wolf : Season 1 Episode 3