 Complete the following phrase:  An avid reader of science fiction, Petri began work on an adaptation of Sheckleys story in 1961; producer Carlo Ponti came onboard the project due to the involvement of Mastroianni. A variety of screenwriters worked on the script to varying degrees without receiving an onscreen credit, including Suso Cecchi DAmico, Nate Monaster and Ernesto Gastaldi. Pontis lack of interest in the science fiction genre led to his mandating of more comedic elements in the story against Petris wishes, including altering its original, pessimistic ending. Backed by ficial support from Joseph E. Levines Embassy Pictures, filming took place primarily on location in Rome and New York City from June to September 1964; produced at the height of the pop art movement in Italy, Petri sought to create a vision of the future that juxtaposes that styles imagery with Romes ancient and modern architectural structures, such as the Colosseum and the 