Alguien Está Mintiendo ( One of Us Is Lying ) is the breakout debut thriller by Karen M. McManus that reimagines the classic "Breakfast Club" trope with a lethal twist. The story centers on five students at Bayview High who walk into detention, but only four walk out alive. The victim, Simon Kelleher, was the creator of the school’s notorious gossip app, About That , and his death is ruled a murder after it's discovered he was about to leak life-altering secrets about the other four. Deep Character Analysis: The "Bayview Four"

An Ivy League-bound overachiever who never breaks a rule—except for the secret Simon held: she cheated on a chemistry test. Her arc focuses on the crushing pressure of academic expectations.

Initially defined by her popular status and dependency on her boyfriend, Jake. After her secret (infidelity) is exposed, she undergoes the most significant growth, evolving into a strong, independent individual.