The medics were on call with plenty of cotton and iodine when silver-screen heavyweights Samuel L. Jackson and Tommy Lee Jones kicked each other's butts in a knock-down, drag-out faux slugfest in their new military action flick, Rules of Engagement.

"That's a great scene," Jackson tells TV Guide Online. "It's exactly what it looks like on-screen." After he and Jones mixed it up, he says, "We were both out of breath, kind of beat and kind of limping and wondering, 'Why the hell did we do this?' "

Jones may have been a formidable opponent, but nothing compared to a certain Southeast Asian tag team: For the film's Vietnam War re-creations, Jackson was shipped off to boot camp. "I reached the point where I [thought], 'OK, this might be fun. We're actually going to play army for a while.' " But Jackson learned that even this pretend army wants you to be all you can be ? and that's an order!

"I figured we'd go out, march around and kind of, you know, load guns, unload guns, take them apart, that kind of stuff. It turned out to be a little different than that. It's intense ? that's Company Vietcong out there!" Right.

In the mud, heat and bug-infested conditions, some of the guys in Jackson's character's company found time to commune with nature. "They were doing the whole 'in the bush' thing," he says, "and they weren't bathing." Talk about your secret weapons.