The problem with a lot of movie sequels is that they are too similar to the original films. Oftentimes, they'll copy the plot and style of the first installment so closely they feel more like remakes than standalone film. But that's never been the case with "Mission: Impossible."

Tom Cruise first turned the classic 1960s TV spy show into a big-screen blockbuster 15 years ago. And while a few key elements have shown up in each sequel -- Cruise, Ving Rhames, identity-concealing masks, and, of course, the theme song -- the subsequent movies have their own look and feel.  Each movie had a different director (Brian De Palma, John Woo and J.J. Abrams, respectively) who put their own stamp on the material. And the sequels brought in new costars, exotic locales and hair-raising stunts to try to top the one that came before.

From the looks of the just-released trailer, the fourth film, "Mission: Impossible - Ghost Protocol," could be the most radical departure yet. Cruise returns as IMF secret agent Ethan Hunt, but this time he's backed by a new team that includes the Oscar-nominated star of "The Hurt Locker," Jeremy Renner. The cast also includes Paula Patton ("Precious"), Josh Holloway (TV's "Lost"), and Simon Pegg (the first actor other than Cruise and Rhames to appear in two "M:I" movies).