Two of science fiction's greatest auteurs, James Cameron and Christopher Nolan, will release trailers for their new original films on August 21. "Avatar Day" will be your first official look at that movie, plus Nolan's ultra-mysterious Inception.

As Cameron announced at Comic Con, you'll be able to go see around 15 minutes of Avatar footage for free, at select 3-D and Imax theaters, on the 21st. But that's also the day that the movie's first official trailer premieres, in theaters as well as online.

But meanwhile, Warner Bros. is saying that Christopher Nolan's next movie, Inception, will have its first "teaser trailer" premiering on that same day, in front of Quentin Tarantino's Inglourious Basterds. Even if the teaser trailer consists only of a few images or a mysterious voiceover, it'll still be 100 percent more imagery than we've seen so far from this movie set within the "architecture of the mind." All we know so far is that Ken Watanabe is blackmailing Leonardo DiCaprio, and Ellen Page is DiCaprio's sidekick. [JoBlo and Slashfilm]