By Clark Collis
September 08, 2016 at 05:42 PM EDT
Darko Entertainment

In the new horror-thriller Happy Birthday, Matt Bush and Riley Litman star as L.A.-dwelling film biz types who take a trip to Mexico and wind up in a boatload of trouble after teaming up with a pair of dubious characters played by Erik Palladino and Matthew Willig. Written and directed by Casey Tebo, the film also stars Britne Oldford and Vanessa Lengies. But in several scenes, the show is effectively stolen by Aerosmith frontman Steven Tyler. This is partly because his character is an eccentrically bearded, magic mushroom-dispensing, shaman named Kasape Suka and partly because, well, he’s Steven Tyler.

“I’ve known Casey since he was ankle-high to a platypus,” the singer tells EW. “Well, not that young, but more than 10 years ago he was willing to take the low-level production jobs for Aerosmith — videotape practice, backstage, anything. So to see his career reach the point it has, how could I say no? He’s worked very hard. He may look like he should be sleeping on the streets of Venice, but he’s the nicest guy. Plus, have you seen the trailer? I get to play a shaman that’s out of his mind, so, yeah, I can’t say no to that! If he asked me to play a bank teller, I’m not so sure.”

See the trailer below, and read on for what Tyler had to say about creating his off-kilter look for Happy Birthday, out in theaters and on VOD Sept. 9.

ENTERTAINMENT WEEKLY: What was the shoot like?

STEVEN TYLER: It was a smaller movie, so everyone is all hands on deck — no trailers, no fancy craft service, just a bunch of people doing what they love for little money because they liked the script and Casey’s vision. That includes me. But you know what? There’s a family vibe on shows like that. It’s like playing clubs when you start out. You carry your own amps, your cousin is selling the T-shirts. It only takes one person for the next step. Clive Davis came to see Aerosmith, the next day he signed us. So maybe the right person sees Happy Birthday, and Casey is doing a studio movie.

How did you prepare to play a larger-than-life character like Kasape Suka?

It’s hard, you know? I had to try and find someone I knew who was kind of like that. I’m still looking! Got any suggestions?

Tell us a little bit about your look in the film.

I was always jealous of guys like Keith Richards, who got to be in Pirates of the Carribbean, so I wanted to go for that kind of look. So much that goes into movies, set design, costume, hair, makeup… I actually grabbed this red hot pepper, which I thought was a prop, and chewed on it, as the character, and two minutes later… you know the rest of that story. Is ring sting method acting? Yeah… so — The beard? Well, the movie is set in Mexico, so I needed some of that Tex-Mex vibe, so I called my buddy [ZZ Top’s] Billy Gibbons and asked him to overnight me a bit of his clippings. We superglued it on my face, and over a year later I’m still peeling that stuff off.