The "Late Show" has become a bit nostalgic as host David Letterman nears his last show on May 20.

Proving that 2015 is the year of the '90s, Hootie and the Blowfish reunited Thursday for a special performance of their first hit "Hold My Hand." It doesn't get more '90s than that!

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"They made their television debut in 1994. Oh my god, is that possible?!" Letterman said upon introducing the band. "Performing the song that started it all, Hootie and the Blowfish."

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"Hold My Hand" was off the band's 1994 album "Cracked Rear View," which went platinum 16 times in the U.S. and ultimately became the best-selling album of 1995. It is also known as one of the fastest selling debut albums of all time, and the Late Show had a little something to do with that thanks to letting the group perform 21 years ago.

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Since their last studio album in 2005, "Looking for Lucky," frontman Darius Rucker has become a successful solo artist in country music. If you listen carefully, you can even hear a bit of his Southern twang come out when he's singing with Hootie.

This '90s group is big on reuniting. They do so annually at their Homegrown charity concert in Charleston, SC. It will be held this year on Aug. 7 and 8.