"And then, as a cry for help, he tries to commit suicide, and the only person the hospital can find a number for is his estranged twin sister Maggie, played by Kristen Wiig, who lives in upstate New York where they grew up. So she comes to retrieve him and bring him home, and he ends up living with her and her husband, played by Luke Wilson."
It's a film that switches beautifully between moments of levity and hilarity, and a real undercurrent of sadness and frustration, which isn't the easiest tone to achieve, but Hader attributes his long-time friendship with Wiig to helping make Milo and Maggie's relationship compelling.
"You have to just kind of trust where you're going with the story, and not think about the tone too much, and it's great to have a wonderful person like Kristen to work with. With her, I was comfortable being very vulnerable, and that was incredibly helpful."
Their natural real-life brother-sister type relationship is not that different from their on-screen one, Hader explains, and there were a couple of scenes where they were left to improvise a certain amount of sibling-type banter.
"The scene in the dental clinic [where Maggie works], that was one scene in the movie where there was a lot of improvising, we were messing around a lot. And that's very much how Kristen and I are in real life - if you hung out with us, that scene is kind of what it would be like. You'd think it would be fun, but it actually gets annoying and old for everyone else really fast. But we were making each other laugh for real."
Director Johnson has called the film "a love story between a brother and sister" (not in a Game of Thrones-type way), and it's a story that just about anyone with a sibling will relate to - how you can have an antagonistic relationship, but also care deeply, and how your shared history creates a tie that you can't break.
"There's one great scene where their mom comes for dinner. Milo doesn't really have that much of a problem with their mom, but Maggie does, and he gets that, but he's gone ahead and invited her over to Maggie's house anyway. I think people find that very relatable," Hader laughs.
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Milo's somewhat flamboyant, emotional style, particularly in contrast to Maggie's handyman husband, provides plenty of laughs, but Hader was impressed that the film didn't focus on Milo's sexual orientation as an issue.
"What I liked about the script was that Milo, being gay, that wasn't his 'problem'. In a lot of movies, it would somehow centre around that, you know maybe he was the only gay kid in the upstate New York town or what have you, but here, Milo just happens to be gay, and he has other bigger problems that he's dealing with."
That doesn't mean Hader didn't have fun discussing Milo's styling with Johnson ("Craig and I would have these long discussions about clothes and hairstyle and accessories - they seem innocuous, but a lot of thought went into them"), or working out dance moves for a scene where Milo tries to bring Maggie out of a dark mood by lip synching to Starship's Nothing's Gonna Stop Us Now.
"That was the only preparation I had to do for the role," Hader laughs, "I had to listen to that song a lot. Filming that scene was a lot of fun, though. Craig kind of mapped out what we could do, you know, the piano is here, Kristen, you're sitting there, Luke, you're standing there, and Bill, you can dance in this general area. And then we just kind of shot it for half a day, me crawling round on the floor, and making up these dance moves."
"And then we broke, and we shot the scene where the police bring me home after I've been on the roof of that building, and I talk about looking my high school bully up online, and how I peaked in high school. So that was very emblematic of the movie, half the day you would be laughing and having a blast, lip synching, and then the other half of the day you'd be shooting a depressing, kinda heavy monologue."
That balance between laughs and tears is what makes The Skeleton Twins the perfect first lead dramatic role for Hader in many ways, but it wasn't something he planned - he's just glad the festival audiences who have seen the film so far, have responded so warmly to his new career move.
"I've never been necessarily crazily fixated on ambition, or planning my career, it never seems to work. I used to do it a bit when I was on Saturday Night Live, thinking 'Okay, this is what I'm going to do next', but fate or other things would always get in the way. But when I relaxed and went with the flow, and ran on instinct, that's when things seemed to open up.
"I think that's pretty much where I'm at right now, so we'll see what happens."
Who: Bill Hader
What: The Skeleton Twins
Where and when: In cinemas from Thursday September 11
- TimeOut
