Mike Flanagan is producing a body horror movie called Rot, and the cast attached to it is the kind of lineup that makes you read the trade twice. Matthew Lillard, Amber Midthunder and Cooper Koch are all on board. Deadline broke the news on Wednesday.
The script comes from Geo Bradley and landed on the Black List, the annual industry survey of the best screenplays nobody has made yet. Alexandra Magistro directs, making this her feature debut. Flanagan produces through his Red Room Pictures banner alongside Molly C. Quinn, Matthew M. Welty and Elan Gale.
A Trauma Cleaner and His Mother’s House
Here is the setup. Rot follows an antisocial man with obsessive compulsions who is haunted by the death of his hoarder mother. He takes work as a trauma cleaner, the job that starts after the coroner leaves, hoping it will force him to face what he has spent his life avoiding. That is not how it goes. The work begins to infest him, and his mental state unravels along with it.
Deadline describes the script as Repulsion by way of Cronenberg, which is a hell of a thing to say out loud. Roman Polanski’s 1965 film is still the benchmark for watching a mind come apart inside its own four walls. Cronenberg is Cronenberg. A hoarder house packed with somebody else’s death is a genuinely nasty place to run that experiment.
The Cast Is the Real Headline
Matthew Lillard is deep into the best stretch of his career. He came back as Stu Macher in Scream 7, he plays William Afton in the Five Nights at Freddy’s movies, and he turns up as principal Henry Grayle in Flanagan’s upcoming Carrie series. Whatever he is doing, it is working.
Cooper Koch has been down this road before. Before Monsters: The Lyle and Erik Menendez Story made him a household name, he led Carter Smith’s Swallowed, a 2022 body horror film we reviewed back in 2022. He is not a tourist in this genre.
Amber Midthunder broke out as Naru in Prey and has been picking sharp genre work ever since. She is also in Carrie, playing gym teacher Rita Desjardin.
Which is the detail the trades skipped past this morning. Two of Rot‘s three leads are coming directly out of Flanagan’s Carrie. He spent a Stephen King miniseries working with Lillard and Midthunder, and then handed both of them to a first-time feature director. That is not an accident, and it says something about how much faith Red Room has in Magistro.
Flanagan Is Producing, Not Directing
This is worth saying plainly, because his name on a horror project sets a certain expectation. Flanagan is not behind the camera on Rot. Alexandra Magistro is, and it is her first feature. What his involvement does mean is that a first-time director gets Red Room’s resources and a cast this strong, which is not nothing.
Flanagan has plenty on his own plate. His Carrie series for Prime Video just dropped a full trailer, and that is the next thing arriving with his name above the title.
One Thing to Keep Straight
There is another body horror film called ROT in the works, and it is a completely different movie. That one is the feature debut of writer-director Cat Del Re, it stars Aurora Perrineau, and it was announced in November 2025 with a heavy emphasis on practical creature effects. Two unrelated body horror movies named Rot is a lot for one genre to absorb in the same stretch, so expect the two to get tangled together.
Per Deadline, Flanagan’s Rot shoots in Vancouver in November 2026. No distributor has been announced.