Haunted (2002)

S1E6 Nocturne

Frank awakens in an unfamiliar apartment next to a badly injured police officer, her condition leaving him puzzled and with no recollection of the past few nights. When she slips into a coma, he finds himself at the center of an Internal Affairs inquiry regarding her assault. Compounding his confusion, he discovers he's been involved in a case that he can't remember at all.