Michelle Obama, Late Night With David Letterman

First lady Michelle Obama makes her debut on The Late Show Monday to discuss her Joining Forces initiative. 

But host David Letterman wanted the real scoop from his guest: In private conversations between the couple, does the president ever bash anyone? "It has never happened," Obama insisted. "He is always upbeat, particularly about Congress."

First Lady Michelle Obama to make her first appearance on the Late Show with David Letterman

Check out a sneak preview of her appearance on The Late Show to find out why she likens Letterman to Oprah Winfrey: