In the adorable clip, the kids are delighted when they realize who's standing behind them

Credit: The Tonight Show/NBC

What do you get when Jimmy Fallon teams up with the Sesame Street characters to play a prank on a few unsuspecting kids? Complete and utter adorableness.

In a new clip, the Tonight Show host teaches the PBS stars a lesson in photobombing: “Okay guys. Be quiet. We’re doing a photobomb. You know what a photobomb is, right?” Fallon, 41, tells Elmo, the Cookie Monster and Abby Cadabby.

“Well, a photobomb is when someone takes a picture and then we jump in the background and surprise them, and then they don’t know that we’re there until they see it on their phone.” (Fallon is quite the photobomb expert – last year he pranked unsuspecting football fans on the NBC Super Bowl red carpet in Phoenix with Chris Pratt and Chris Evans.)

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The comedian and his friends then took turns popping up in the background, pulling funny faces and posing while the unknowing kids were being snapped away, and Count von Count and Ernie eventually joined in on the fun.

Watch the clip to see the kids’ adorable reaction when the realize what’s going on behind them.

The Tonight Show Starring Jimmy Fallon airs weeknights (11:35 p.m. ET) on NBC.