The Threat Assessment Unit investigates the home of a young actress after she is frightened by an obsessed fan. Meanwhile, Beth receives an unsettling personal letter and Perry gains more access into her life.

Psychiatrist believes he is being stalked by a suicidal patient, but the TAU unravels a tangled mystery exposing the suspect and the great lengths he has undertaken to terrorize his victim. Also, Beth's private investigation into her own stalker leads to a stunning revelation.