Among the pulsing throng of fans belting out the catchy beach rock of Mac DeMarco at recent his Atlanta gig? The cast of Netflix’s Stranger Things. DeMarco was joined on stage by Finn Wolfhard, who plays Mike Wheeler in the series, for a duet on DeMarco’s “Still Together” at the Tabernacle.

Wolfhard, 14, has proven himself a DeMarco fan before, posting a cover of the singer’s “Salad Days” on Twitter last October. Upon hearing it, DeMarco told Pitchfork, “You know, I liked it and thought that it was great. I have texted with him a little bit, and he’s a really nice dude. It’s pretty wild. I like the show, too. He’s so young!”