The town identified as "Upton, California" in the opening is the same town identified as "Cloverdale, Utah" in the opening of The Case of the Lucky Legs (1959).
There is a community named Upton in California, near Mt. Shasta.
The stock shot of Upton is actually Pine Avenue in Long Beach, California.
On the sales agents' board in Tom Stratton's real-estate office, the leading salesman is one "Vasser". Charles Q. Vassar was the set decorator for this episode.
This story includes Louise Fletcher's second guest appearance on Perry Mason. Her first appearance was in The Case of the Mythical Monkeys (1960).