Dead Fall (The Quantico Files #2)
Nancy Mehl

When it becomes clear that the killer is targeting agents in Alex's unit, they are ordered into lockdown, sheltered in the dorms at Quantico. Alex bunks with a controversial agent, Kaely Quinn, who has returned after being dismissed three years earlier. As they work together, Alex discovers in Kaely the role model she's never had, despite being warned away.
As Alex questions who she wants to become, things get personal when the brilliant killer strikes close to home. Now Alex will do anything to find the killer--even at the risk of her own life.