Sergio Leone, bored of the Italian film industry's reliance on swords 'n' sandals epics, reckoned he could make a Western by ripping off the plot of Kurosawa's
and casting that guy off Rawhide as his anti-hero.
The stylish, sadistic 'Spaghetti' Western became a viable genre in its own right, and revolutionised Hollywood's own output as directors from Peckinpah to Leone's star, Clint Eastwood, ramped up the politics and violence. When you think about it, Leone's flippant tone, with its laconic one-liners and unstoppable hero, foreshadowed the modern cinema action hero.
If It Didn't Exist:
Nobody would have thought to heighten a gunfight with close-ups of nervous eyes or whistling on the soundtrack.