'M3GAN' required reshoots to get a PG-13 rating.

The new sci-fi horror film tells the story of a killer doll that becomes overprotective of a young girl and director Gerard Johnstone explained how some scenes were toned down to make sure that the movie could be seen by younger audiences.

The director told Total Film magazine: "Making it PG-13 was something that happened after the fact, but it was always close to PG-13 anyway.

"It seemed kind of a mistake not to embrace it. I even remember thinking early on, 'This could be PG-13, and some of my favourite films like 'Drag Me to Hell' are PG-13.' So we made the decision to go PG-13 and actually reshot a couple of things."

Johnstone felt that the reshoots actually improved the quality of the film, which stars Allison Williams and Violet McGraw, and pointed out that other successful horror flicks such as 'Get Out' have had the "tamer" rating.

He said: "What I was really stoked about is that when we reshot those scenes, they were more effective. It's like, 'Yes, you do have to cut away at certain times', but it's fun having to rely on sound and suggestion so much."

Johnstone explained that he realised during filming that the changed scenes would make more of an impact on those watching the movie.

He recalled: "I remember turning to my sound designer after a re-do and just saying, 'Holy s***, that's worse.' We were trying to get this PG-13 rating and I was like, 'That is so much worse than what we had before.'"