It may have been a “dumb bet” but it made a great episode. The I Spy episode “Bet Me a Dollar” aired on this date, February 16th, in 1966. Kelly decides to get “lost” for awhile and Scotty makes a bet that he can find him. Normally it would be some fun and games except that Scotty really has to find Kelly after finding out that Kelly is infected with anthrax from a knife wound he received from helping break up a street fight.
A very similar plotline was used in the Starsky & Hutch episode “The Game” in 1978.
Early in the episode, after Kelly gets his wound patched up and before the anthrax is discovered he plays it up for his date. It works…until he forgets to keep up the act.