From The Perry Mason TV Show Book
Perry is attending a bar association dinner when Daniel Conway approaches him to say he's just found his rival's secretary, dead. Conway is sure he is being framed for murder. He's involved in a vicious proxy war with Warner Griffith over Cal-Texas Exploration.
Perry thinks he can solve this one in a jiffy, and tries to corral Griffith into a confession. He's surprised and puzzled to get an ironclad alibi instead. That doesn't stop Perry from finding a unique, if weird, witness who has a photographic memory and can identify people by their shoes.
We see a very dapper Perry in this episode (check out his bow tie). Also, watch the sparks fly between Perry and Della during this case.