May (Louisa Krause) and Drew (Sophie Lowe) are sisters who go diving at a beautiful, remote location. When May is struck by a rock, leaving her trapped 28 meters below, with dangerously low levels of oxygen, it is up to Drew to save her life.
From this fairly simple set up, writers Maximilian Erlenwein (who also directs) and Joachim Heden conjure up a thriller that is often extremely suspenseful. All Drew’s desperate actions as she tries to find help, get more oxygen to her sister, and find inventive ways of freeing her make sense in the moment. That really kept the story believable and made me root for the pair.
May and Drew’s troubled back story is neatly established early on. Unfortunately, once May is trapped, we get a number of flashbacks and hallucinatory scenes depicting their childhood. Not only do they not add anything to the story, each one releases the tension that has been built up.
There is a neat twist towards the end, though, and at 90 minutes it rattles along nicely.
Rating: 7 out of 10