Danny DeVito won his role of Fly Speck because he and Kirk Douglas' son, Michael Douglas, were best friends and had been roommates in college.
Françoise Pascal was first offered the part of Lucy-Ann. But she turned down the role so she could do The Iron Rose (1973).
Anne Douglas took over producing duties on the movie when her husband Kirk Douglas became overworked and overwhelmed with directing, co-writing and starring in this picture according to an article published in the 27th December 1972 issue of show-business trade-paper 'Variety'.
Actor-director Kirk Douglas hired his wife Anne Douglas as producer, his son Eric Douglas as a stills photographer and son Peter Douglas as a producer's assistant, whilst the Douglas Family pet, a Labrador retriever Shaft played the dog "Beau". Son Michael Douglas was not involved. Kirk Douglas once said "So if this film stinks we've got the whole Douglas family to blame." He added, "My phone doesn't ring any more. I have to find my own work."