Mandy Moore, carrying over so much goodwill from the adorable TV drama This Is Us, stars as Lisa, a recently single worrywart living in the shadow of her cooler sister (Kate, played by Claire Holt of The Vampire Diaries and The Originals). Right from the visually playful opening scene, the pair strike up a genuine-seeming rapport, which carries the film through some wobbles later on. Suffice it to say: things go very badly, in some entertaining and scary ways. If, at any point, you thought that it was safe to go back in the water, the submerged segments here will make you question that decision. In the dark abyss of the ocean’s lowest depths, writer-director Johannes Roberts, and cinematographer Mark Silk, show some real flair for crafting unsettling shots. Using underwater cameras, handheld torches and some stellar composition, they build tension with real confidence. One particular sequence – where Moore is surrounded in all directions by utter blackness – verges on masterful. It’s an image that sticks with you long after the credits roll. When the much-advertised finned foes actually appear, they look jarringly fake in comparison to the genuine terror that’s been brewing. However, if you’re willing to suspend your disbelief a bit, and buy into it, there’s still a lot of fun to be had in the final third of this film. Speaking of fun, there are a few moments of real levity to look out for here as well. The film doesn’t forget that it’s built on a playful sibling dynamic, and some big laughs are thrown in to break the tension on occasion. Roberts, in collaboration with Ernest Riera, has put together a very impressive script here. And work it does. You’ll come out of this wanting to see Roberts given a bigger budget to play with (he’s got The Strangers 2 next), and hoping to see more of Moore at the cinema in the years ahead. She’s a very charming screen presence, with an impressive array of facial expressions, which is vital in keeping us engaged in this holiday of horror. Holt does a fine job as the less-loveable half of the central double act, and the above-sea-level supporting cast – notably Matthew Modine as a boat captain – does just enough to make an impact in their short appearances. But Moore is very much the star, and the wonderful crafting of tension is very much the main event. It’s probably the advertised shark attacks that will lure people into the cinema for 47 Metres Down, but, funnily enough, those are probably its weakest element. It’s the moments of the humour, the family drama, the performances, and the build up that work best. Although there’s a sense that it could’ve been much more with a bit of extra cash thrown at it – with better and more frequent shark attacks, they wouldn’t have needed to pad out time with constant oxygen tank discussions – 47 Metres Down is a fun night out at the pictures. Just be prepared to be petrified on your next trip to the seaside. Again.