See 16-Minute Sneak Peek of "Avatar" Free

To promote his futuristic thriller, "Avatar," James Cameron is issuing free IMAX 3-D tickets for a 16-minute preview of his film on Friday, USA Today reports.

The footage, the majority of which was shown at Comic-Con last month, is meant to introduce the alien world of Pandora and to make it clear that the film is a hybrid of live action and computer-generation, not animation.

"There are human people, living in a world no one has ever seen, working in a conceit you have to explain to people," said "Avatar" producer Jon Landau. "You want to give people an idea of what to expect in a movie. You manage their expectations, because their imaginations run wild."

The film's release date isn't until Dec. 18 so the screening could create months of online buzz in the meantime.

The $240 million Fox movie is the first film directed by Cameron since 1997's "Titanic." For that blockbuster, Cameron released a four-minute trailer, twice the normal length.

Beginning today, fans can go to AvatarMovie.com to reserve two tickets and locate IMAX theaters. The extended "Avatar" trailer will also play before and after IMAX showings of "Harry Potter and the Half-Blood Prince." At most theaters it will run twice between 6 and 9 p.m.