Peter Sarsgaard arrived on movie screens over the weekend as both a macho Marine in "Jarhead" and a gay screenwriter in "The Dying Gaul." It's a coincidence that the big-budget war flick and the Sundance indie opened on the same Friday, but that his characters are complete opposites is all part of the actor's master plan.

"I've always wanted to play a lot of different characters," Sarsgaard explained. "You wouldn't think that if I played John Lotter in 'Boys Don't Cry,' who rapes and kills, that I could then play Chuck Lane in 'Shattered Glass,' who brings justice to this kind of intelligential crime."

But he did, and won acclaim in both movies. And Sarsgaard's resume only expands from there, with diverse roles in movies such as "Kinsey" (ambitious bisexual research assistant) and "Garden State" (slacker).

Although "The Dying Gaul" will likely get lost in the shadow of "Jarhead," the movie has garnered Sarsgaard some of the best reviews of his career.

"It's tough to explain," Sarsgaard said of the movie, which also stars Campbell Scott ("Singles," "The Exorcism of Emily Rose"). "Basically [my character has] written this screenplay that's based on real events on my life. My lover just died, I'm gay, this screenplay has two gay characters. It's called 'The Dying Gaul' and [Scott's producer character] buys it, but he buys it for a million dollars under the condition that I will change it to a heterosexual script. So then I agree to do that after a lot of bribing. And it's just about people doing little things that they shouldn't do, little lies to themselves and other people, little betrayals that gradually build up and eventually create their own tragedy, and it becomes a horrible tragedy. But for about the first half, it's funny."

"There's lines in it like, 'No one wants to see a movie about gay people that has gay characters in it,' and I think a lot of [filmmakers] definitely understand that feeling of having a big Hollywood producer tell you it's impossible because America can't handle it morally. I know I'm just sick of movies being pushed to the side because they're not in the moral mainstream. I think the moral mainstream kinda sucks."

Playwright Craig Lucas, who wrote the 2002 movie "The Secret Lives of Dentists," penned "The Dying Gaul" and also made his directorial debut with the movie.

"It makes me less nervous than someone doing their second film," Sarsgaard said of working with a first-timer. "A person doing their first film wants your input because they're scared sh--less and I think that's always good. It's collaborating, and at least if you fail, you fail together. Instead of agreeing [in the case of a second-time director] to do this person's vision, which is because they have a lot of confidence from doing their first movie and they're kind of a dictator. At least I'll have a good time with a first-time director."

Sarsgaard constantly went to Lucas with suggestions for his character, down to the scarf he wears throughout. On the other side of the coin, he was also constantly taking things in from Lucas and especially his co-star, Scott.

"He's fantastic," Sarsgaard said. "The thing with Campbell, there aren't many actors who if they ask what time it is [in a scene], you actually check your watch. You go, oh, my line is 'six o'clock.' But with Campbell, he initiates a response from you, which makes my job easier."

Sarsgaard has also appeared this year in "Skeleton Key" with Kate Hudson and "Flightplan" with Jodie Foster.

Check out everything we've got on "Jarhead." and "The Dying Gaul."

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