Watch the trailer for Ang Lee's 120 fps film 'Gemini Man'

Will Smith battles... young Will Smith.

We knew Will Smith was preparing to fight a younger version of himself in the upcoming Ang Lee sci-fi film Gemini Man. Now, thanks to the trailer released today, we get a glimpse of what that will look like. The two-minute clip shows present-day Smith as Henry Brogan, an elite but aging assassin who's being chased by a younger clone. Visual effects -- similar to those that allowed Samuel L. Jackson to digitally de-age in Captain Marvel -- will make it possible for Smith to play both roles.

When the film hits theaters on October 11th, the action shots could look hyper-real, as Ang Lee is shooting the film in 3D at 120 frames-per-second (fps) and 4K resolution. There's a chance theater chains might not be able to screen it in that format, in which case we'll have to settle for watching a Smith-versus-Smith action drama.