Early in "Thank You for Smoking," protagonist Nick Naylor (Aaron Eckhart, in a breakout role) sits down for an interview with journalist Heather Holloway (Katie Holmes). "My other interviews have pinned you as a mass murderer, blood sucker, pimp, profiteer and my personal favorite, yuppie Mephistopheles," she explains with a flirtatious smile. Nick, you see, is a charismatic, congenial fellow who makes his living as a spokesman for Big Tobacco. He's damned good at his job, too. The first time we see him, he's getting booed on the Joan Lunden show. A few cunning words later, he's shaking hands with a cancer-afflicted teenager, having convinced him that cigarette companies have no reason to wish him ill: Why would they want to lose young customers?

Director Jason Reitman's "Thank You for Smoking"-based upon a book by Christopher Buckley-is a satire every bit as sharp and likeable as its grinning protagonist. Everyone is skewered here: well-meaning politicians, ruthless journalists, Hollywood execs. Reitman resists the temptation to over-moralize, making for a more thoughtful film. We never forget that smoking is bad-we never approve of Nick's job-but we root for him through the last. Adding to the film's complexity is the role of Nick's son Joey (Cameron Bright), who struggles to understand why and how his father does what he does.

"Smoking" moves at a fast clip, clocking in at just over 90 minutes. The best bits of humor come from the lines, which are quick and clever. At the start of the film, Nick tries to explain his greatest talent, his charisma: "You know the guy who can pick up any girl? I'm that guy … on crack." Not all of the jokes work quite as well, and the story drags a bit in the middle, but for the most part the film keeps a good pace-it's speedy when it needs to be an slow when it needs to be.

Front and center in "Smoking"'s impressive cast is Eckhart, who pulls off the part of Nick so well that we suspect he'll be a household name very soon. Eckhart oozes charm from every pore when Nick is "on," but he's even more interesting when we get to watch him struggle with the "moral flexibility" that his job requires.

William H. Macy is brilliant (as always) playing Nick's antagonist, a Vermont senator who campaigns earnestly against smoking, but fails to engender the same warm and fuzzy feelings as his counterpart. Also funny are Maria Bello and David Kochner as lobbyists for the alcohol and firearms industries, respectively. Together with Nick, they call themselves the M.O.D. Squad-M.O.D. standing for Merchants of Death.

"Smoking" is a rare film that makes you laugh even as it makes you think. It's less about smoking than it is about the little hypocrisies that make up our daily lives. Spokesmen for Big Tobacco aren't the only ones who play with moral flexibility.