8. Juno & Sarah - The Descent
The original end of The Descent, the version shown everywhere but the U.S., has Juno presumed dead after a fight against the cave monsters, while Sarah has a dream of escaping before waking up and realising that she's still trapped inside with the crawlers moving closer, just as the film ends. We assume that they both die, except that the American distributors, a) realising they might have a franchise on their hands and b) wanting to appeal to the more flowery outlook of stereotypical Americans, changed the ending, cutting Sarah awakening and ending the movie with her escaping. This, of course, paved the way for The Descent Part II, with Sarah alive, while Juno has somehow managed to survive inside the caves. This is also the singular instance on this list of a film being tinkered with post-original release, simply to placate another territory.