George Clooney was once attached to direct, produce, and star in this film for a number of years during its early developmental stages but do to the project staying in "development hell," Clooney eventually dropped out of the project of directing & starring in it to pursue other film projects but has remained on as a producer for the film nevertheless.
Tom Cruise originally bought the rights for his newly revamped United Artists and had Christopher McQuarrie draft a screenplay.
An Italian movie, with the same title and starring Leonard Mann and Gabrielle Tinti, was released in 1986.