Go behind the scenes of the Sundance body-horror comedy Mum, I’m Alien Pregnant with the cast and directors in this candid, gooey interview.
Expanded from the short film HELP, I’M ALIEN PREGNANT, the feature film Mum, I’m Alien Pregnant recently landed at Sundance with a splash of neon slime. A comedy body horror that blends lived experience with outrageous imagination, the film follows a messy millennial underachiever who becomes accidentally pregnant by an alien (well, half-alien to be exact). She must contend with skeptical doctors, a useless baby daddy, and her relentlessly oversharing mum. It is a film that sits in the uncomfortable, hilarious, and visceral space where millennial messy meets extraterrestrial biology.
In this insightful conversation, directors Sean Wallace and Jordan Mark Windsor (the duo known as THUNDERLIPS) join cast members Hannah Lynch, Arlo Green, and Yvette Parsons to peel back the layers of their practical effects-driven production. From the live surgery performed on a malfunctioning prosthetic to the specific color-coding of alien slimes, the team discusses how they transformed the trauma and beauty of birth into a wild, cinematic ride.
For writer and director Jordan Mark Windsor, the inspiration for this story came from a very grounded place: witnessing the birth of his own child.
“Having been a participant and witness to my baby mama’s experience, I was shocked by how little attention doctors paid to her,” Jordan explains. He noted a “shocking and bizarre” disparity in how medical professionals treated him versus his partner.
Beyond the social commentary, the film taps into the universal human urge to share birth stories – a genre of conversation Jordan finds endlessly fascinating. “The movie is, in ways, our group attempt at participating in that conversation about birth that everyone’s always having,” he says.
The film relies heavily on physical, practical effects rather than digital wizardry. For Arlo Green, wearing the prosthetics was a heavy but helpful experience that removed the need for much imagination.
“When they put it on me, I didn’t have to do much work. I sort of just looked down and freaked out,” Arlo recalls. The logistics of the alien anatomy were so complex that Arlo had to “stuff things down his pants” to maintain his character’s physicality when the prosthetic wasn’t in use.
Director Sean Wallace detailed the evolution of the alien design from the original short film, explaining that they wanted to push the “cinematic tension” further. This led to a “gender ambiguous” design that featured multiple stages of arousal, including a unique “flap” that required three people to operate simultaneously on set. “We were trying to work on the like sci-fi-ness of it all to a form of showmanship,” Sean notes.
Hannah Lynch, who plays the protagonist Mary, spent weeks as “the gooeyest, slimiest human” on set. Despite the cold and the smell of the slime, she found the physical discomfort helpful for her performance.
“The intensity was great because it contributed to the physical turmoil that the character was going through,” Hannah says. The production even went so far as to color-code their fluids: alien semen was blue, Mary’s internal alien-hybrid blood was purple, and vomit had its own distinct consistency.
The Final Takeaway: What Do You Hope People Experience?
Yvette Parsons: “I think I just I want people just to have a really good laugh. I don’t think it’s possible not to, while watching this film. I’ve never seen anything like it or heard of anything like it.”
Jordan Mark Windsor: “I really want people to be thinking maybe in the back of their mind the whole way through, maybe she’s going to change her mind. But I love that this character does not change her mind… I think there’s a favorite takeaway, that there’s going to be a weird limbo at the end.”
Sean Wallace: “I think we’ve been saying all along that we want people who haven’t been through birth to feel sick and people who have given birth to feel seen.”
Hannah Lynch: “The thing I love about this movie is that I often find that the, you know, the greatest tragedy can be best communicated sometimes through comedy… it’s intensely terrifying and horrific and painful for my character… but what I love about this movie is that we do it in this other way that kind of you’re laughing and you’re cringing and you’re kind of screaming.”
About Mum, I’m Alien Pregnant
When a messy millennial underachiever accidentally gets alien-pregnant she must overcome sceptical doctors, a useless baby-daddy, and her oversharing mum in order to survive and reclaim her life.
Mum, I’m Alien Pregnant played at Sundance 2026.
