The 1978 'Superman' film made a bold move. During the closing credits, four words appear on screen "NEXT YEAR: SUPERMAN II." Over the next three decades, this gimmick was used time and time again. More often than not, when a movie boasts a sequel, it never happens.

Here are 10 examples of sequels we were promised, but never got to see.

10. 'The Adventures of Buckaroo Banzai Across the 8th Dimension' (1984)

Right before the film's famous closing credits sequence (which was copied by Wes Anderson for 'The Life Aquatic') there’s an announcement for the next installment: 'Buckaroo Banzai Against the World Crime League.' Sadly, this sequel was never made. But acclaimed geek author Ernie Cline (who wrote the movie 'Fanboys' and the novel 'Ready Player One') started his career by writing a script. More recently, Moonstone Books published a series of Buckaroo comic books written by creator Earl Mac Rauch. So there's still hope we'll see Buckaroo, New Jersey, Rawhide and the rest on the big screen again.