(NEXSTAR) – Jimmy Fallon and Jimmy Kimmel pulled the ol’ switcheroo for April Fools’ Day.

TV viewers who tuned in for “The Tonight Show” or “Jimmy Kimmel Live!” were treated to a surprise on Friday night when the other Jimmy walked out from behind the curtain to deliver the monologue.

“Hi, I’m Jimmy,” said Fallon, who was greeted with cheers from the studio audience at the El Capitan Entertainment Centre in Hollywood where “Jimmy Kimmel Live!” is taped.

“Please, please, settle down. You’re going to offend the other Jimmy,” he joked. “Happy April Fools’ Day, everybody!”

Over in New York City, Kimmel joked that at least some of the “Tonight Show” studio audience at NBC Studios in Rockefeller Center might be bummed by his presence.

“Show of hands, how many of you are disappointed?” he asked. “Be honest.”

The two Jimmys were game to take over each other’s signature bits, too, with Fallon participating in a “Mean Tweets” segment (retitled “Sweet Tweets” for the night), and Kimmel writing Fallon’s “Thank You Notes.”

Fallon’s guests for the evening included Justin Timberlake and Kimmel’s own Aunt Chippy (who reportedly had no idea Fallon was going to hosting “JKL!”), while Kimmel welcomed Hugh Jackman and comedian Bridget Everett. The Red Hot Chili Peppers was the musical guest for both shows.

Each show’s house band, however, stayed with their respective city.

At the end of their respective monologues, both hosts spoke to each other via satellite to discuss how the prank came together.

“We’ve been talking about this for a long time, I was just telling [the audience],” Kimmel told Fallon, explaining that the two conceived the idea in April 2020.

“I love that we did this. I can’t believe we pulled it off. I really can’t believe it,” Fallon said.