It's one of the most memorable 'Late Show With David Letterman' moments.
It was a birthday present that left David Letterman thankful.
In 1995, Drew Barrymore made a memorable appearance on the Late Show With David Letterman when she flashed the host on his 48th birthday. Now, with Letterman's last episode set to air later tonight, the actress is looking back at that unforgettable moment.
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“He's always been known as the person who had no problem letting the audience know he was not down with what the guest was doing," Barrymore told Entertainment Weekly. "It was scary."
Barrymore also shared that her dance routine was "completely spontaneous and not calculated in any way." At the time, it left Letterman saying, "I can't thank you enough for that."
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And their chemistry only continued afterwards. Barrymore explained, "Then I just looked forward to going back. There's an energy to his show. The more you tried to charm him, the less he wanted it. He either liked you or he didn't. When you usually go on a talk show it's very buddy-buddy. But with him you have to work for it. But not too hard, because he won't like that!"
Letterman is retiring after 33 years as a late night host. Comedian Stephen Colbert is set to take over the chair as the Late Show's host.
Check out the video below to see ET's top 10 moments with David Letterman.