The genesis of this film was quite complicated. The Modesty Blaise cartoon strip had been running in the London Evening Standard newspaper for several years; it was the work of Peter O'Donnell and Jim Holdaway. O'Donnell, who had devised the character, was approached to write a film script based on Modesty's adventures and Sidney Gilliatt was set to direct. It was part of the deal that O'Donnell would turn his script into a book-of-the-film novel for publication at the same time as the film's release. However, there were delays, Gilliatt dropped out, Monica Vitti replaced Julie Christie as Modesty, and Joseph Losey was - to the great surprise of everyone - signed as director. Losey ordered many changes to the script, O'Donnell left the project in high dudgeon, his novel version appeared before the film, and many fans of the comic strip attacked the film as a travesty, although it was a box-office hit in Europe. O'Donnell wrote several more Modesty Blaise novels, which were very popular; however, the film inspired no sequels.