Kevin Spacey in Se7en, Johnny Depp in 21 Jump Street, Samuel L Jackson in the first Iron Man - many actors take uncredited roles during their lucrative careers. It's a seemingly bizarre career choice, and one that you could easily fail to see the logic behind, given the lack of acknowledgement in the credits of their commitment to the role. But, of course, that's only half the story.
Spacey did it for shock value - giving the audience no inclination of his involvement until he appeared on screen; Depp did it for a nostalgic chance of revisiting an early career success and Jackson's role was to wet the appetites of the audience for future Marvel movies. Most actors take uncredited roles for the chance to take part in a project that looks like fun, without the hassle of press-tours and the risk that the movie bombs, or simply as a favour to another film-maker. There's also the possibility that producers might take smaller, credited roles into account when deciding how much to pay an actor, so remaining uncredited could protect financial interests.
Naturally, there have been cases where an actor's presence (even in a minimal role) can overshadow the entirety of the film: Brad Pitt was no more than a cameo in 12 Year's A Slave, and yet the Italian poster relegated Chiwetel Ejiofor's main protagonist to secondary status while Pitt's more famous face was presented like the hero, overshadowing the message of the movie entirely.
For those reasons and more, the uncredited role has become a staple of cinema and, while most are designed for the audience to notice the big names rocking up in the film, sometimes the role is so obscure that it can be easy to miss. With that in mind, we're celebrating ten of the most famous uncredited cameos that you may not have noticed.