Justin Timberlake paid a visit to his good friend Jimmy Fallon on The Tonight Show on Wednesday, October 26, and the pair reprised their hilarious Camp Winnipesaukee sketch, this time singing Alanis Morrissette's "Ironic." Check out the awesome musical moment in the video above!

The sketch — which is really just an excuse for the pair to channel their inner nerd, put on wigs and sing a song like "Jumper" by Third Eye Blind or "Africa" by Toto — began with the pair in their beds at camp in 1996 as Fallon asked his curly-headed pal what he was going to be for Halloween.

"It's a TV character," the "SexyBack" singer said.

"Steve Urkel?" Fallon asked, before guessing again and coming up with Saved by the Bell's Zack Morris.

"No," said Timberlake, pulling a face.

"Blossom?" asked the Saturday Night Live alum.

"Yes!" yelled Timberlake.

The pair then began to sing "Ironic" and had trouble keeping a straight face as they recited the lyrics and harmonized loudly, attracting the attention of Mr. Fletcher, the camp counselor.

As soon as Fletcher left the room, they began giggling and sang some more, leading to Fletcher's return.

After shooting him in the shorts with their water pistols, the pair finally decided to try to get some sleep but not before Timberlake said, "Hey Jimmy, best friends forever?"

"Best friends forever," Fallon replied. (Cue the "aww" noises from the audience.)

Later in the show, the pair took on the Best Friends Challenge to prove how well they know (or don't know) each other.

Watch the video below to see how many times Timberlake and Fallon struggle to keep it together and stop laughing.

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