Joaquin Phoenix's reinvention of himself as a burnt-out, drugged-up, fallen celebrity has come to an end with the release of "I'm Still Here"—the hoax documentary chronicling his faux downfall. Some liked the film, some didn't. In any event, the best moment of Phoenix's protracted ruse came during his clammy, bewildering appearance on the Late Show with David Letterman in 2009. Bringing it all back home, Phoenix returned to the Late Show last night and apologized for the stunt.

"You've interviewed many, many people and I assumed that you would know the difference between a character and a real person, so - but I apologize," Phoenix said. "I hope I didn't offend you in any way."

Here's the clip from last night followed by his original appearance with Letterman: