Things aren't going well for Dr. Mark Collier, a psychiatrist who specializes in hypnosis. He's stealing drugs from his clinic to use in an experiment with his disturbed patient, Nadia Donner, but he's not getting the results he wants. Nor is he getting them from the lab experiments conducted by his harried research assistant. It seems his book, which is dependent on these results, will fail. Far worse, he's having an affair with Mrs. Donner - and Mr. Donner finds out. The husband confronts these two illicit lovers at his beach house, but in an angry moment Dr. Collier kills him with a fireplace poker. Collier convinces Mrs. Donner to lie to the police and claim that two intruders killed her husband. But can she convince the rumpled, redoubtable Lt. Columbo that she's telling the truth?

This is one of the few Columbo episodes where the original murder is a spontaneous act. In most episodes the murder is carefully planned.

Charles Whelan:
[watching a rat in a maze] They remind me of my junior assistants!


Dr. Anita Borden:
We call her Willy.


Charles Whelan:
I don't have a Willy.