Teen Wolf Season 1, Ep. 05 "The Tell"

A video store clerk is changing light bulbs on a ladder. Lydia and Jackson are outside, trying to decide on a movie. While Lydia stays in the car, Jackson goes inside and finds the clerk with his throat ripped out. Horrified, Jackson hears growling and hides behind one of the shelves before peering out to see the eyes of the Alpha. The Alpha knocks down the shelves and Jackson is pinned to the floor. The Alpha almost attacks him but notices the claw marks on the back of Jackson's neck left by Derek. The Alpha then breaks through the window and runs off past Lydia, who screams in panic. Scott and Derek are up on the roof of the video store, where Derek shows Scott what the Alpha has done. Derek reminds Scott that the Alpha will kill him unless they team up to fight it. That morning, Allison receives a necklace with her family crest on it from her aunt Kate as a birthday present. Scott convinces Allison to skip school for the entire day for her birthday, to which Allison accepts. At school, Stiles is worried about Lydia because she is absent. He visits Lydia, who is loopy on pills, and finds a video on her phone of the Alpha jumping through the window at the video store with glowing red eyes. Stiles eventually decides to delete the video. Derek must deal with the hunters on his own, resulting in a confrontation with Kate. Stiles's father visits the vet with blurry security camera photos of the Alpha breaking through the window, running in the parking lot, and then appearing in the shape of a walking man. The vet acts oddly upon seeing the photos and it's hinted he may be hiding something. At Parent-Teacher Night, a description of Scott, Allison, Lydia, Jackson, and Stiles is given, revealing new information about each of them. Allison's father and Scott's mother find out that they have skipped school. Scott and Allison arrive, knowing they are in deep trouble. Just then, an unseen animal runs through the parking lot. The panicked crowd scatters and there is chaos before Allison's father shoots it. Everyone walks up to surround the dead animal and it turns out to be a mountain lion.