Milton Selzer co-starred in a 1964 episode of The Twilight Zone called The Masks (1964). In it, as well as this episode of The Wild Wild West, Selzer's character wore a mask which was central to the story line.
At 38:45, as West enters the hotel, cues from "The Plot", by Lalo Schfrin can be heard on the soundtrack. This was heard weekly on Mission: Impossible, also on CBS.
Set in the town of Paradox, Nevada.