In the Shadow of Evil.

Jack Brenner is a hot-shot cop on the trail of a serial killer known as The Roper. Just as he's getting close to catching the killer, he is injured and develops amnesia. Dr. Molly Nostrand works to help Brenner recover his memories and the two become romantically involved. Meanwhile, The Roper is still out there somewhere and the police are depending on Jack Brenner to bring him in.