Keegan-Michael Key On Improv, Easter Eggs, And Whether It's A Hat Or Toad's Head In The Super Mario Bros. Movie

There's a lot of stuff happening on screen, particularly in that whole scene where Toad takes Mario on a tour of the Mushroom Kingdom. Did you have any idea what was going to be happening on screen?

No ... when I read the script, the ad-libs — all of the ad-libs and all that special stuff — not all of that was in there, so one of my favorite things is when the guy walks past the antique shop. You hear the two guys in the antique shop, and he is like, "Are you sure this is going to work?"

"Yeah, yeah. If it doesn't, just blow on it." Just blow on it? Like those old cartridges. That was great. All those little ad-libs in there are fantastic.

Were there any other Easter eggs? There's a reference to "Punch-Out!!" in here.

Oh my gosh ... I'm sure I missed 95% of the Easter eggs. I do remember ... the "Punch-Out!!" one is in the game. It's not in the Mushroom Kingdom world. It's in the regular world. It's in the pizzeria or in the shop. I couldn't even tell you. I've probably missed ... I have to go back and watch the movie two times in a row and start looking for them.

I was curious because improv is your thing, and you're so good at it. Does it differ when you're doing voice work?

It does differ. You want to stay as on track as you can, even if you're getting to improvise. You want to stay on track because the story has to go where it's going in regard to how it's being animated. That's the hardest ... I should say, that's the fun challenge of it, that you're trying to make sure that you're staying within the confines.

Now, sometimes you're lucky enough — or you're privileged enough — to get people animating after your voice, so then you get to ad-lib a little bit more. That's a blast. That's really fun when the director goes, "All right, we're reanimating that line. Okay, we're reanimating that line," so it differs [from] when you're on camera, and you can just go for it.

"The Super Mario Bros. Movie" will hit theaters on April 5, 2023.

This interview has been edited for clarity.