Robert Conrad and Anthony Eisley previously co-starred in the 1959-63 crime and adventure series Hawaiian Eye (1959).
Robert Conrad went on to play a homicidal health club magnate named Milo Janus in An Exercise in Fatality (1974).
Artemis Gordon does not appear in this episode. Ross Martin appears in credit only as he was recovering from a heart attack.
The mortician's name is Swanson; in the previous episode Jim Backus played a mortician named Swanson.
Jeremy Pike's undercover identity, Baron Klaus Esterhazy, is like a play on French Major Esterhazy who was the Dreyfus Affair from 1894 -1906.