There’s only one more season of Stranger Things left and while Finn Wolfhard and the rest of the cast are currently busy promoting other projects, the hit Netflix series is still what everyone wants more details about.

During an appearance promoting When You Finish Saving the World on The Tonight Show, Finn Wolfhard discussed what exactly went down during the incident where he figured out the Duffer Brothers’ planned spin-off for the show. “We were on set filming Stranger Things 4 and we were all talking about if there’s going to be—like joking, ‘oh they’re all going to have us back in 20 years and we’re all going to fat and old,’ that kind of thing,” he said, referencing doing the ultimate Stephen King homage of bringing back their crew when they’re grown up. He continued to explain an idea he hit on in that moment. “And then I was like, ‘But if you guys are actually going to do a spin-off, it should be this.’ And then I said it and the Duffers looked at each other and looked at me and they were like, ‘Could we talk to you for a second?’ And then they pulled me off and they were like, ‘That is the idea. Who told you?’ and I was like, ‘No one,’ and they were like ‘What do you mean? You just came up with it?’ and I was like, ‘Well, no, I just thought that that would be a cool way to expand.’ It was really funny and they were like ‘Okay, well... don’t tell anyone.’”

Who knows when we’ll know what the plot for the spin-off is, as the wait for Stranger Things 5 (due out next year)is already going to be long enough. When asked how he was feeling about the end of his Stranger Things era, Wolfhard shared, “It’s going to be crazy once it’s all done. I’m just excited to go back and actually finish it.” He also reacted to finding out the name of the first episode was “The Crawl” along with the rest of the world, despite the fact that he’s actually on the show: “I’m not even joking, I found out about that yesterday. A lot of people don’t believe it, they’re super cagey.”

Watch more of the interview below!

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