Sister Lorna, who is a nun at the school where she works, disappears just before she is to take her final vows. Sister Amelia hires Hammer to find her. Her former husband, Donnie, had just been released from prison and her body was found in his apartment. The race is now on to find Donnie, who was a participant in a payroll robbery which netted $400 000, money that was never found. When he is murdered the trail runs cold. It turns out that Sister Lorna had hidden a key to a locker in a puppet and the murderers were after it.