Pretty Little Liars (2010)

Premiering in 2010, "Pretty Little Liars" is a teen drama and mystery series drawing from Sara Shepard's young adult novels. The show centers on four friends whose group disintegrates after their leader, Alison, vanishes. A year later, they start getting messages from an anonymous person known only as "A," who threatens to reveal their private secrets, including some they believed only Alison knew. The series spanned seven seasons, with its narrative exploring themes of friendship, deceit, and the challenges of growing up under constant surveillance.

The series blends mystery elements with typical high school drama, focusing on the girls' attempts to uncover "A's" identity while navigating personal relationships and the impact of the past. Its storyline incorporates various subplots common to the teen drama genre, but with an underlying suspense as the threats from "A" escalate. With 161 episodes, the show delves into the long-term consequences of secrets and the dynamics within the core group of friends.