Christian Bale and Steve Zahn will star in "Rescue Dawn," an action drama by Werner Herzog and based on the director's acclaimed 1997 documentary, "Little Dieter Needs to Fly."

The project, which has been coming together in fits and starts during the past year, begins shooting in Thailand in mid-August.

The film recounts the true story of German-born Dieter Dengler, who dreamed of being a pilot and eventually made his way to the United States, where he joined the military during the Vietnam War era. He was shot down over Vietnam and captured. Eventually he organized an escape with a small band of captives.

Bale will play Dengler, and Zahn will play an ill-looking and bent POW.

Producing are Gibraltar Entertainment's Elton Brand and Steve Marlton, Cameo FJ Entertainment's Freddy Braidy, Franceso Julliard and Elie Samaha.

Co-financing are Spice Factory and Werner Herzog Prods.

Gibraltar International is the sales agent.

The film has no domestic distributor.

Herzog's latest film, "Grizzly Man," is a documentary on grizzly bear activists Timothy Treadwell and Amie Huguenard, who were killed in October 2003 while living among grizzlies in Alaska.

Bale, repped by Endeavor and attorney Carlos Goodman, next appears in Terrence Malick's upcoming "The New World."

Zahn voices Disney's upcoming animated feature "Chicken Little" and appears in the feature "Bandidas," opposite Salma Hayek and Penelope Cruz. He most recently starred in "Sahara."

Zahn is repped by Endeavor, Principal Entertainment and attorney Frank Stewart.