Adapted by Terence Frisby from his own play. The Broadway production of "There's a Girl in My Soup" opened on Oct. 18, 1967 at the Music Box Theatre and ran for 322 performances. Gig Young and Barbara Ferris were in the original cast.
Peter Sellers as Robert Danvers injures his eye and says "I can't see anything. The string in my eye's gone." Most audiences miss the humor in this line. Seven years earlier, in the film Dr. Strangelove, Peter Sellers as Group Capt. Mandrake says (seriously) "The string in my leg's gone," to explain that he has a bad leg due to a damaged hamstring. In this film, the line is funny because the eye does not have a hamstring. It's also funny because it breaks the fourth wall by acknowledging that he is the same actor who said a similar line in a different movie.
Robert's car is a 1965 Rolls-Royce Silver Cloud III drop-head coupe by Mulliner Park Ward. This car was owned by Peter Sellers at the time. In 2020 these cars can be worth into six figures - and this one, owned by Sellers, even more.
Goldie Hawn in an interview many years later, described Peter Sellers, her co-star on this film, as being "strange".
The opening credits list an "assistant to the director", "assistant to the assistant director" and "assistant to the assistant's assistant".