The producers of M3GAN went to extreme lengths to ensure audiences can't tell if the killer robot was played by an actor or not.

In an interview with Total Film, M3GAN director Gerard Johnstone revealed that neither he nor anyone else involved with the film is allowed to talk about how exactly the sinister doll was brought to the screen. Asked whether a real actor, animatronics, CGI, or a mix of all three was applied, he only revealed that it was a "multi-tiered approach." On the topic of whether child actor Violet McGraw, who plays the niece of M3GAN's creator and the doll's protégé, bonded with the artificial character on set, Johnstone replied: "She did, but I would also say that she was relatively creeped out by M3GAN as well."

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M3GAN is an upcoming sci-fi horror film revolving around an artificially intelligent life-sized robot girl programmed to befriend and support Cady, a young girl recently orphaned following her parents' death in a car crash. Eventually, M3GAN becomes over-protective of Cady, with bloody consequences for everyone the robot deems a threat to the girl's well-being. The film gained a high grade of anticipation after releasing two creepy trailers hinting at the movie's sinister story.

M3GAN was co-produced by horror moguls Jason Blum and James Wan, who are in advanced talks to merge their companies Blumhouse and Atomic Monster. Wan is also credited with coming up with the story, while Malignant writer Akela Cooper penned the screenplay. Johnstone is best known for his debut feature, the 2014 New Zealand horror comedy Housebound which was a hit with critics and festival audiences.

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Wan is no stranger to the killer doll subgenre. He previously directed Dead Silence in 2007 and helped launch the Annabelle franchise. Creepy dolls also play essential parts in some of his other films, including the Saw series, which made him an instant force in the horror field. While he has moved on to bigger blockbuster franchises like the Fast & Furious and Aquaman movie, he is still a prolific producer of low-budget horror.

M3GAN enters a crowded market of creepy dolls and killer robots but it looks like she will be welcomed with open arms. Chucky creator Don Mancini has already expressed his openness to having M3GAN and Chucky meet for some crossover mayhem.

M3GAN opens in theaters on Jan. 6.

Source: Total Film