Ginny's life comes to a screeching halt one fateful Monday morning when a shooter invades Southwestern High School. In lockdown with both the homeroom sub and her secret crush Owen badly wounded, Ginny finds herself teamed up with Kayla, one of the "Barbies." They must try to keep their classmates alive amid terror and pain. With the uncertainty of everyone making it out alive growing with every minute, there's only one thing Ginny knows for sure: no one is making it out unchanged.