One week deep into the 2016 Fantasia International Film Festival and one of my favorites so far is about a guy who goes on a spiritual retreat and vomits up a creature. Well, it’s also about the negative baggage we carry inside us and what happens if we can’t let it go. And how this baggage affects those around us. And about the complexities of dating. So yeah, Bobby Miller’s debut feature The Master Cleanse isn’t your typical horror comedy. It packs one hell of an emotional punch in its honest depiction of a group of people on the ultimate path of “purification.”

Bobby Miller first wowed audiences at Fantasia a few years ago with his short film Tub, which you can watch on his website (I insist you do). For The Master Cleanse (read our review), Miller expanded on Tub‘s concept in a way – taking something psychological and turning it into a physical creature. It’s a simple idea on the surface, but it’s given great weight by the fantastic practical puppets Miller and his team utilized to personify the character’s inner demons. And those characters are played by an amazing ensemble: Johnny Galecki, Anjelica Huston, Anna Friel, Oliver Platt, Kyle Gallner, Diana Bang, and genre veteran Kevin J. O’Conner (who recently played Yellow Card Man in 11/22/63).

Miller was generous enough to take the time to talk with me about The Master Cleanse, where the film came from, working with practical puppets, what one should bring to Anjelica Huston’s house, and more. The film is a personal one for Miller, who actually tried to write while taking the real 10-day master cleanse. “Six days into it I couldn’t write. I couldn’t even be a person. But the film came out of a real place of depression and me trying to figure out how to deal with it. I feel like the melancholy and the darkness of both Tub and The Master Cleanse comes out of trying to figure who the hell I was and dating in New York is really hard. Like if I wasn’t the one who was screwed up, then it was the other person who was screwed up. There were a lot of near misses with relationships.”

Being a personal film, the story was bound to change as Miller was writing it. He did, however, always have the same ending in mind. And believe me, it’s a powerful one, which means it had to be earned. “In the first draft, Johnny’s character was a journalist who had heard about the master cleanse and he wanted to see what it was all about. As I kept writing it, I realized that in order to earn that ending, it had to come from a more emotional place. We needed to care about Johnny, care about him as a person. So all the rewrites were about getting more to the heart of it and earning that ending.”

Johnny Galecki’s heartbroken character Paul is the beating heart of The Master Cleanse and thanks to him, the film was able to get the small but tremendous ensemble it has. “I had originally cast someone else in the lead role. Johnny had really loved the script and wanted to produce it. He stepped in as a producer and then there was a scheduling conflict with the original lead, so Johnny stepped in. It’s weird now to even think of the original actor in this role. Johnny was just so committed to it. He came in and then the script went around. Anjelica was the next person who came on board and it was completely surreal. Me and Johnny went to her house and we didn’t know what to do. She’s Hollywood royalty, so what do we do? Bring wine?

We had this great meeting with Anjelica and afterwards she popped champagne and I was like, oh shit! We were just so giddy. From there the rest of the cast came together. Even the smaller roles are so great. Like Kevin J. O’Conner (Master of Illusions, There Will Be Blood), he’s been in a ton of genre films. We got a really eclectic cast I’m so happy with. And it really all came from Johnny’s involvement.”

The other major characters in The Master Cleanse are the creatures – physical manifestations of the actor’s emotional baggage. What an awesome concept. Miller explained that he was inspired by the actual master cleanse. “Honestly, I was just fascinated with the idea that you could expel negativity from yourself. With Tub, I was exploring the concept of an idea turning into a creature or something tangible. So it was the idea of negativity turning physical. There’s something I find interesting about taking a psychological thing and turning it into a puppet.”

The puppets themselves are adorable, though depending on the character’s inner demons, they can be really off-putting as well. They were brought to life through a combination of old school practical effects and puppeteering, as well as CGI touch ups in post. Miller himself is a big fan of the medium, but it wasn’t without its challeneges. “I love puppets, so it was a complete joy to work with them. As far as challenges, they just take a long time and they break down. There’s a scene where someone is giving their creature a drink and the water seized up the animatronics’ gears. A lot of the time, with the CGI touch ups, they could just figure it out on the spot. But with the practical effects, there’s a lot more planning ahead of time and you’re limited to what an actual puppet can do. In my mind, these creatures were crawling around everywhere and doing a lot more stuff.

Even though there’s only so much you can do with the puppets, they bring something magical to the set. When the actors see them, they just light up. They become like little kids when the creatures come out. There’s something in the air that you can’t get if they’re just talking to a stick with a tennis ball on it.”

For his next project, Miller is teaming with producer Alicia Van Couvering (Cop Car) for a dark comedy in the vein of Election and Ghost World. They hope to shoot sometime next year. In the meantime, The Master Cleanse continues its festival run. Check out dates and more about this amazing movie on its website.