Hobbs and Shaw actress Vanessa Kirby is seen in one of the main promo images for shark horror movie 47 Meters Down, yet isn't actually in the film. When it comes to shark flicks, it's no secret that there's basically Steven Spielberg's 1975 masterpiece Jaws, and everything else. That's not to say that there aren't other worthwhile examples of cinematic shark attacks, but Jaws is so good that most filmmakers don't even attempt to compete with it, instead just hoping to make a worthwhile contemporary.

One of the most successful instances of shark horror in recent memory is 47 Meters Down, which swam into theaters into 2017, a time that almost feels like a decade ago at this point. Released by Entertainment Studios - a company much more well-known for distributing syndicated TV shows - 47 Meters Down wasn't a critical darling, although its reviews were more average than awful. What made 47 Meters Down a certified smash was its low $5.5 million budget, as it earned over $60 million in theaters, a huge return on investment for a movie that almost went straight to home video.

Related: Best Shark Horror Movies (& Where To Watch)

47 Meters Down was assisted by a pretty aggressive marketing campaign for a smaller release, but what few seemed to notice is that one of the most often seen images from said campaign didn't actually feature stars Mandy Moore and Claire Holt. Instead, Vanessa Kirby is pictured, which seems weird, until one knows the relevant backstory.

Why Vanessa Kirby Is In 47 Meters Down Images Despite Not Being In The Film

Vanessa Kirby in Fast and Furious Presents Hobbs and Shaw

Prior to actually filming 47 Meters Down, in fact, before the full script had even been written, writer/director Johannes Roberts shot a short teaser designed to sell the concept to potential international buyers. It featured one female diver underwater with a menacing shark. That diver was played by Vanessa Kirby, a British actress who's become quite famous in the years since the teaser was shot, but at the time wasn't well-known. By the time 47 Meters Down finally got released, Kirby was playing Princess Margaret on The Crown, and has since appeared as the White Widow in Mission: Impossible - Fallout and Hattie Shaw in Fast and Furious' Hobbs and Shaw spinoff movie.

The thing is though, Kirby was never actually attached to star in the final 47 Meters Down movie, she just took part in the teaser. However, for reasons unknown, the marketing department at Entertainment Studios used an image of Kirby from the teaser in a full-face diving mask as the main still for 47 Meters Down, despite her not actually being in the movie proper. It's a striking photo to be sure, but amusingly enough, most people didn't even seem to notice that it wasn't Mandy Moore or Claire Holt pictured. Roberts himself did and would go on to humorously point out the discrepancy when promoting the sequel 47 Meters Down: Uncaged.

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