The ever-present flies in the end sequence are an in-reference to the actual flies that plagued the production. Fruits and vegetables were present throughout the sets on location in Spain, and were often left to rot in the sun at the end of the shooting day.
Budgeted at an estimated $2 million; film rentals in the U.S.A. were $3 million.
Soundtrack:
- "Comedy Tonight," Written by Stephen Sondheim, Performed by Zero Mostel and Ensemble.
- "Everybody Ought to Have a Maid," Written by Stephen Sondheim, Performed by Zero Mostel, Michael Hordern, Jack Gilford and Phil Silvers.
- "Bring Me My Bride," Written by Stephen Sondheim, Performed by Leon Greene, Zero Mostel and the Ensemble.
- "Lovely," Written by Stephen Sondheim, Performed by Annette Andre and Michael Crawford.
- "Lovely" (Reprise)," Written by Stephen Sondheim, Performed by Zero Mostel and Jack Gilford.
- "The Dirge," Written by Stephen Sondheim, Performed by Leon Greene and Ensemble.
- "Comedy Tonight (Reprise)," Written by Stephen Sondheim, Performed by Zero Mostel, Michael Crawford, Annette Andre, Patricia Jessel, Michael Hordern, Leon Greene, Buster Keaton, Jack Gilford, Phil Silvers and the Ensemble.


A Funny Thing Happened on the Way to the Forum