Obsession has very quickly become the horror movie the whole world is talking about.

The second feature-length offering from YouTuber-turned-filmmaker Curry Barker, Obsession centres around two friends who enter a nightmare scenario when one of them makes a life-changing wish for the other to fall in love with him “more than anyone in the fucking world”.

A modern-day “be careful what you wish for” cautionary tale, the film has received rave reviews, including an enviable 96% critical score on Rotten Tomatoes and 4.2 stars on Letterboxd, with particular praise for its break-out star Inde Navarrette.

But despite dominating the pop culture conversation right now, how much do we really know about what went into Obsession’s creation?

Here are 17 behind-the-scenes secrets you’d probably never heard about how the film of the moment came together (and be warned – there are plenty of spoilers ahead)…

The story goes that Curry Barker first had the idea for Obsession after inviting his friends over to watch an episode of It’s Always Sunny In Philadelphia that he had a small role in.

“Before the episode [aired] there was a Simpsons episode where [Bart] has a monkey paw, and he’s making wishes and stuff,” he recalled to Triple J, referring to The Simpsons’ second Halloween special Treehouse Of Horror II.

In the episode – based on WW Jacobs’ short story The Monkey’s Paw – the family travels to Morocco and buys a cursed monkey’s paw at a market, which grants their wishes with sinister consequences.

Curry admitted: “I was just excited to see my Always Sunny episode, but it hit me right then and there on the couch that Obsession idea that I had would be perfect if it was a wish movie.

“And so I actually remember the moment, I remember being on the couch, and being like, ‘oh my god’ and writing. It down. And after that, I just kept developing and developing that idea.”

He also told Variety: “I was thinking that I’ve never seen a straight crazy horror [based on that idea]. We’ve seen ‘be careful what you wish for’ tons of times. But we’ve never seen my version of it. I instantly started thinking about what I could do with that…”

“I didn’t want to use the Monkeypaw because it was too recognisable,” he told IndieWire. “And so then I went down this rabbit hole of trying to find things that you could make a wish off of.

“You’ve got the wishing well, you have shooting stars, a wishbone you break in half, but nothing really worked well for the movie.”

In the end, he reasoned: “Screw it. I’m going to make something up.”

He told Moveable Fest: “My mum actually helped me design that. She’s a graphic art designer, and I told her I wanted it to look kind of timeless, like it’s from the ’50s or the ’80s, and I wanted it to have this very retro feel, like it’s been around forever and you can’t really pinpoint when it was made.

“I also wanted it to look inviting, and almost creepy in the way that it looks so friendly, like it couldn’t hurt anything.”

Remember that cringe-worthy party scene where Nikki makes everyone uncomfortable by, among other things, reading out an excerpt of an incestuous love story based on Hansel And Gretel?

Well, it turns out, it was written by Curry’s dad.

The director told Polygon: “My dad had just started his screenwriting journey and I was like, ‘Yeah, if you want to give it a stab’. So I let him write it and he did some really creepy stuff.”

“My dad’s been a writer for a while,” he added. “My dad writes novels and stuff, and now he’s a full-time screenwriter. And my dad has a mind that lends itself well to that type of creepy stuff. So I guess like father, like son.”

Well, Curry said he wanted that to be a manifestation of Nikki’s mind warping different kinds of love, having previously considered Bear to be a brother figure to her before his wish for her to fall in love with him.

“I knew I wanted it to be about Hansel And Gretel,” he said during his Polygon interview. “I knew that I wanted it to be about brother and sister because the kind of thing I was doing there is that if you remember Nikki tells Bear in the beginning of the movie that she kind of sees him as a brother.

“And so that’s kind of that, like brother and sister being together. It’s not right and it’s not supposed to happen, but it is. And that’s kind of the movie.”

“Nikki’s movement was something that Curry and I built from scratch,” Inde told The Hollywood Reporter. “Not because we didn’t want to take any inspiration. It was just as soon as we got attached to the project, we just really spearheaded. It was a fast track.

“We filmed it in 26 days, and it was an indie-budget film, so we didn’t have a lot of things at our disposal. But that created this organic movement for me.”

She continued: “I’m not a movement person. I’ve never really done that before. I used to dance, but Curry would be on the opposite side of me, mimicking something with his body, and then I would do it in a way, and be like, ‘No, no, like this’. And so we would mirror each other.”

“Technically, the choreographer would be Curry Barker,” she added with a laugh.

In fact, the team relied on good old-fashioned makeup contouring to achieve Nikki’s unsettling look.

“I think they call it contour in the makeup world, but you can kind of just accentuate things,” he recalled to Polygon.

“The goal was never to make her look too demon, because if you go demon, then you’re just making her eyes really dark and her mouth really dark, and then you’re in that uncanny valley. We wanted her to still look human but not quite human. But also, it was 90% her.”

“I was so impressed with the art department to see what they did with that,” Curry beamed. “What’s funny is we were shooting so out of order that sometimes we had to take that duct tape down to shoot one scene and then put the duct tape back up to shoot another scene.

“So, what the art department did to make it really easy is, 90% of that duct tape is not taped to the door. It’s like a big sheet. So there’s a big sheet and then tons of tape. And so the only tape that’s attached to the wall is on the outskirts. Once you remove that, you can kind of remove this big piece that they had designed. It was really smart.”

In the original cut, the scene where Nikki smashes in Sarah’s head with a brick was much more graphic, but to ensure the film got a wider release, Curry had to make some tough decisions.

“That was definitely a scary moment for me as a director,” he admitted to The Guardian. “Especially as I had just watched the movie in Toronto with a crowd that really reacted to that scene.

“Hearing the news that I might have to cut it down was quite devastating at first. But we cut it down and I feel like the integrity of the scene is still there … I’m actually surprised at how much they let us keep in.”

Similarly, Inde insisted to The Hollywood Reporter that version of Obsession shown at TIFF was “not that different” to what we all saw in cinemas.

“[When] I kill Sarah, we reduced the amount of head smashes because it was too long,” she claimed.

“I really loved the response at TIFF, because people really liked how long it is and how aggressive Nikki is. It shows how obsessed she is, what she’s willing to do for Bear and how far she’s willing to take it. It’s just really intense.

“Also, what was cut was the aftermath. Curry wanted to play with the idea of what does a human body do after that sort of smashes, like there’s gurgles come out, so there was gurgles, there was like human sounds that might have been too gruesome for an R rating, so they kind of downsized it.”

She added: “TIFF definitely got a really gruesome, gruesome version, but it sounded like they liked it.”

“The original opening of this movie was actually at Bear’s house [when he found] the dead cat, and you’re just thrown in and you don’t really know what’s going on,” Curry told Movable Fest.

During the editing process, he “decided to open” up the story, bringing back actors Michael Johnston and Cooper Tomlinson to shoot the new opening set at a diner.

In the version of Obsession that made it into cinemas, Bear’s hold over Nikki comes to an end when he dies, at which point she screams in terror when she realises what she’s done.

Before Nikki became horror’s new “final girl”, though, Curry had planned for the character to die alongside the rest of her friendship group.

“I was really obsessed with this Romeo And Juliet ending, actually,” he told Entertainment Weekly, revealing that it was his dad who told him to have Nikki live, instead.

“We shot both,” he noted. “We shot this ending that you see in the movie, and we shot the ending where she ends it all.”

He added: “We had shot a ton of different versions of the official ending, the one that’s in the script, the one that I was excited about, and I was like, ‘Okay, we’ll do one ending where [Nikki] survives, but we’ll just do one take of it, and then we’ll move on’.”

Because of the complicated technique used to capture it – and the fact that Curry was still set on Nikki dying – he recorded the ending that made it into the finished film in one take.

“It was a very technical shot, and so we only gave her one where she survives,” he told Entertainment Weekly, revealing that Inde’s “performance was so good” he had to include the scene in his movie.

He revealed: “I just remember my dad and multiple people around me being like, ‘Dude, I think it’s way more disturbing if she just survives this thing’. I was like, ‘Ah, you’re right’. And so we switched it.”

Inde told The Hollywood Reporter: “The original ending was that I was going to choose that I didn’t want to live that way anymore, after all of the trauma and pain. [At the] last second, they were like, ‘Let’s just try this one thing’, and from other people’s perspective, which is high praise for me, and I really, really appreciate it, they did one take, they felt like it was magical and electric, and they knew that that was the ending.

“At the end of all of this, it was such a release to get all of what I felt like Nikki was experiencing out of my body. I’m really glad that she didn’t die. I’m really glad that she’s considered a horror final girl, that I think is the sickest title ever.”

“There was a version where Sarah tells Bear that Nikki admitted to her that Nikki actually had feelings for Bear,” Curry recalled to Polygon. “I thought that was really heartwrenching if it turns out that Nikki liked Bear along and then this happened, but that obviously didn’t make it in.”

He also pointed out: “No one ever has picked up on this, but there’s this line in the beginning that says Nikki was crying in the break room. You can hear it at the trivia bar. They talk about, ‘Why was Nikki crying in the break room?’ And Ian’s like, “I don’t know, maybe she…” But really it’s because Ian had told her that he wanted to [end their casual hook-ups].”

“I wanted to shoot this centre-composed and have extra head space because I wanted it to feel uncomfortable in its loneliness,” he told Variety.

“There’s something about centre-composed that forces you to look and pulls you in in a way that traditional composition may not. I’ve seen a lot of horror filmmakers I look up to recently shooting in that way.”

“He just makes some bad decisions but I think it starts from a really innocent place,” the director told The Guardian. “It’s what he chooses to do after that that’s bad.”

He also noted: “Embarrassingly, I wasn’t even familiar with the term incel until someone brought it up to me.”

You know that part where Bear calls up an operator for the One Wish Willow helpline?

“It was me,” Curry admitted to Polygon. “I recorded that dialogue in my room, way after we shot the movie. I was editing in my room so I was able to just do whatever I wanted with it. I just got my phone out and I was just like, ‘Hey, what’s up?’.”

Curry has claimed he’d “definitely” be up for another film set in the Obsession world, but introducing a different set of characters and, crucially, another wish.

“It wouldn’t have these characters, but it would have the One Wish Willow,” he teased to Polygon. “It would be [about] that same selfishness of a person who wants something that’ll only benefit them and not really thinking about other people.

“The horror would come out of what happens when you wish for something that you think is going to be good, but it’s not. That’s the theme, and so there’s so many different stories.”

During her Hollywood Reporter interview, Inde also revealed that she’d “absolutely” be up for playing Nikki again, even though she “really” loves the idea that the story is “kind of left there”.

“It’s like a memory, whenever you look back to yourself at like 24, 23, 22 those are all chunks, and they begin and end at a certain point. I think that’s kind of like this story. It begins and it ends, and then it’s new Nikki, if you will,” she added with a laugh.

Obsession is in cinemas now.