'Snowden' releases dramatic first teaser trailer

A dramatic first teaser trailer for Snowden has been released.

The preview does not include footage from the film, but instead traces Edward Snowden's path from Army recruit at age 20 to National Security Agency whistle-blower and "the most wanted man in the world" at age 29.

Snowden is directed by Oliver Stone (JFK, Nixon), and opens in theaters Dec. 25. Joseph Gordon-Levitt stars as Snowden, with Shailene Woodley as Snowden's girlfriend Lindsay Mills and Zachary Quinto, Scott Eastwood and Nicolas Cage also confirmed for roles.

The movie is based on The Snowden Files by Luke Harding and Time of the Octopus by Anatoly Kucherena. The real-life Snowden, now living in Russia, faces up to 30 years in prison for leaking classified information about the NSA's surveillance program.