Despite his extensive on-screen time as the scruffy sailor, Mr. Grimes, and a powerful performance which is strikingly different from his Perry Mason role, Raymond Burr is not listed in the closing credits as Mr. Grimes. Apparently the studio thought the usual closing credit which simply says "Raymond Burr as Perry Mason" was enough.
The murder victim is named Otis Swanson. In the Columbo episode "Last Salute to the Commodore", the commodore who was murdered is also named Otis Swanson. Jackson Gillis is credited as the writer in that episode as well as this one.
Raymond Burr, also played a dual role in his second successful series - In an episode of Ironside, Burr played an artist named Duffy.
When Burr's alternate-character, "Grimes" who speaks with the Cockney accent, is being shaved, close to the beginning of the episode, the barber shaving him hums a familiar tune. It's the recurring melody and principal theme in the second movement of Beethoven's Fifth Symphony.
This was Dan Tobin's last appearance as restaurateur Terrance Clay.