Annie Le, a brilliant Yale PhD student, vanishes days before her wedding; CCTV cameras catch Le entering her research lab but there's no trace of her leaving; the FBI uncovers a dark secret that exposes the shocking truth behind her disappearance. 

Eight veterans die mysteriously at a VA hospital; after conducting hundreds of interviews, poring over medical charts and electronic records and exhuming the victims' bodies, the FBI discovers the killer comes from inside the hospital itself.