Buick Motor Division provided George Barris with a new 1963 Riviera to customize. The Villa Riviera was originally created by Barris for use as his personal car. The story of the car's onscreen use began when director Leslie H. Martinson was visiting the Barris shop in North Hollywood to look at a vehicle that Barris Kustoms was building for another film. Martinson was quite taken with the Villa Riviera all decked out in cherry red paint over a fire frost white pearl base. He quickly signed a contract that included a clause to repaint the Buick white so it would show up more clearly when filmed. It was used in the movie For Those Who Think Young (1964) featuring a young Nancy Sinatra and James Darren. Later the car was used in this episode.
Frank Gillett's Buick Riviera's license plate (DEM 265) will be seen again on other characters' cars in at least three future episodes: The Case of the Bouncing Boomerang (1963), The Case of the Thermal Thief (1965), and The Case of the Golden Venom (1965).
Strychnine comes from the Strychnos nux-vomica, a tree native to southern India, Sri Lanka, and Indonesia.
Perry takes the unusual step of having his client testify at the hearing.
The music playing on the phonograph at the funeral home is a performance of 'Ich Ruf Zu Dir, Herr Jesu Christ', BWV 639 by Johann Sebastian Bach performed on organ.