‘Big Bang Theory’ costars Kaley Cuoco, Johnny Galecki ‘just leveled up’

Big Bang Theory fan favorites Kaley Cuoco and Johnny Galecki have reunited, not on set, but for a playful game night with a tech twist.

The duo, who dated off-screen during the hit sitcom’s early seasons, appeared together in a humorous new ad for a mobile game, shared on both of their official Instagram accounts on Tuesday, April 15.

"Game night with @kaleycuoco just got a serious upgrade thanks to @royalkingdom," Galecki captioned the post.

Cuoco chimed in with her own playful take, writing, "Game Night with @sanctionedjohnnygalecki just leveled up."

The video kicks off with Galecki bursting into Cuoco’s home and dramatically tossing her board games out the window.

"Those are my games!" she protests, before Galecki introduces her to the game on his phone. A few swipes later, Cuoco is hooked, expressing, "Oh wow, that is fun, you're right. We don't need these games."

Cuoco later commented on the video, "This was so fun to shoot! Back together with my buddy JG."

For the unversed, Galecki starred as lovable physicist Leonard Hofstadter on The Big Bang Theory, while Cuoco played his next-door neighbour and eventual love interest: Penny