The film was originally very different than the completed film. Valerii stated that the film was originally titled Arissa Ballerina and written by Adriano Belli. Valerii commented that "In short, everything was the opposite of what Hitchcock recommended, that is, that characters must ignore what the viewer knows. I told the producers I would make a film out of that script, because it just made no sense!" Gastaldi and Valerii re-wrote the script, but struggled as the Tunisian co-production signed on to Belli's script. Gastaldi's contribution added new motivations for characters and included a few new scenes such as the battle between two bulldozers. Valerii wasn't initially happy with casting Pamela Villoresi, stating that "Sometimes you have to make do with compromises or economical limitations, Villoresi is a very good actress, but I wouldn't cast her as a terrorist, if it weren't for a pre-signed agreement."
