A Tyrannosaurus rex lumbers forward, belts out a deafening roar, then stomps overhead, and a viewer watching inside a virtual reality headset turns around to see the beast walking away.

The lifelike run-in with a prehistoric monster comes courtesy of prototype Oculus Rift goggles, giving a glimpse of a future that breaks movies out of the flat screen.

Virtual reality, which immerses viewers in 360-degree worlds long used in video games, is drawing top Hollywood filmmakers and studios such as Twenty-First Century Fox and Walt Disney Co. The technology should arrive on the consumer mass market within two years.

Virtual reality can transport audiences into the middle of the movie landscape, says Brendan Iribe, chief executive of Oculus, which Facebook Inc acquired this year for $2 billion.

“In some decade or two, we are going to be at a point where watching things on 2D surfaces is going to feel pretty outdated,” Iribe told Reuters.

Virtual reality still has technological hurdles to overcome. The biggest problem is motion sickness in some users, which Oculus believes it is close to resolving.

Hollywood directors are trying to figure out how to create 360-degree scenes, and it remains unclear if audiences will want to spend two hours in a virtual world, or just visit for shorter experiences.