Take a look through photos of Keith Urban and Nicole Kidman at red carpet and industry events over the years, and you’re bound to notice a theme: These two are always holding hands.

Their physical affection is a sweet testament to their enduring love for each other — and it also created the opportunity for one hilarious prank during a date night at the Met Gala in New York City.

Urban explained how it all went down during a recent stop on The Tonight Show Starring Jimmy Fallon.

He was there to promote his new studio album, High, but he also revealed how Fallon helped him pull off an epic prank on Kidman while she was rapt in conversation with someone else.

“I was sitting next to Nic and she had her hand on mine, and she was talking to somebody,” Urban recounts. “Jimmy came over and talked to me, and I said, ‘Jump in the seat, Jimmy, and just slide your hand under mine so she’s holding your hand. She won’t know. She’s chatting to somebody, looking the other way.'”

So that’s exactly what they did. Fallon surreptitiously took Urban’s place in the seat, and slid his hand into place under Kidman’s. Sure enough, she had no idea, until Urban sidled over into her frame of view and waved to her.

“And she’s like, ‘What’s going on?! Jimmy, don’t do that,'” Fallon chimes in.

Elsewhere during his conversation on The Tonight Show, Urban opened up about the process of making his new album and shared a cover performance of Sabrina Carpenter’s hit pop song, “Espresso.”