Actor Paul Rudd was shooting his latest film in Washington, D.C. While he was there, he ran into our nation's president -- and things went downhill after that. Paul was shooting 'How Do You Know' -- a movie where he plays a corporate executive. He and co-star Reese Witherspoon then went to the White House, where they met President Barack Obama.

So, what was that like? On 'Late Show' (weeknights, 11:35PM ET on CBS), Paul gave us the straight dope. While talking with David Letterman, the actor discussed a tale of ritual humiliation that took place within the Oval Office.

As soon as he met President Obama, Paul broke out into a "flop sweat." Then, the president asked what his role was in the movie. "I'm playing this guy," Paul said. "He's getting indicted, his whole world is falling apart." " ... Oh, so you're playing a Congressman," Obama said.

Paul then corrected the commander-in-chief, saying that he was actually playing a businessman. Next, Obama said this: "It was a joke." Oh! Jokes are good. We like jokes! Paul Rudd -- you have officially been busted by the President of the United States of America.