It's Only Money (1962)

He's a public howl as a private eye!

Cast

Jerry Lewis, Joan O'Brien, Zachary Scott, Jack Weston, Jesse White

Overview

Lester is a clumsy and awkward TV repair man who is nevertheless gifted technically. In helping out a friend, he is drawn into a mystery involving a missing heir in a rich family. He begins to notice little things, like how much those family portraits look like him. Surely..no..he can't be...can he ?