Teacher's Pet (S01E04)

Buffy's biology class takes a terrifying turn when their new substitute teacher, who appears stunningly beautiful, is revealed to be a giant praying mantis in disguise. The shocking twist comes after the mysterious teacher eliminates the former instructor. As Buffy and her friends investigate, they must uncover the truth behind this otherworldly creature before it targets more victims, all while navigating the challenges of high school life.