Tonight saw the debut of Paramount Pictures' first full-length trailer for "Captain America: The First Avenger"-a full day ahead of its scheduled premiere. Entertainment Tonight first aired the trailer on its website, which was quickly picked up by Spinoff Online, where fans can view an HD version of the spot.

Set during World War II, "Captain America: The First Avenger" stars Chris Evans as Steve Rogers, an 90-pound Army washout who takes an experimental Super Soldier Serum to join America's fighting forces overseas. The new trailer focuses largely on Rogers' transformation into the Sentinel of Liberty and includes several new scenes of Cap in action.

Hop over to Spinoff to view the HD trailer, and enjoy an extensive gallery of screenshots below.

Directed by Joe Johnston, "Captain America: The First Avenger" stars Chris Evans, Sebastian Stan, Hugo Weaving, Hayley Atwell, Toby Jones, Stanley Tucci, Richard Armitage, Natalie Dormer, Dominic Cooper, Neal McDonough, Tommy Lee Jones and Samuel L. Jackson. It opens on July 22.