A passenger jet travelling from the USA to Mexico hits a flock of birds en route, causing the plane to crash into the open ocean. Trapped inside an air pocket hundreds of feet below the surface, the survivors debate whether to wait for rescue or try swimming for the surface. Then the sharks turn up.

The sharks always turn up. To be completely honest, I was somewhat relieved when they did. It would have been a shame to make a film out of such a winning concept and not have sharks also involved. No Way Up is a functional, sufficiently entertaining B-movie that knows exactly what it wants to be and fulfils its obligations to the audience accordingly. Is it good? I’m inclined to write “no”, but at the same time if viewers want an underwater thriller about forgettable passengers on an aeroplane getting picked off one by one by a swarm of computer-generated sharks, well then I’m not sure there is a superior option.

Sophie McIntosh plays Ava, daughter of a prominent American politician, who is trying to go on a private vacation with her boyfriend Jed (Jeremias Amoore) and friend Kyle (Will Attenborough). Unfortunately for Ava her risk-averse father has insisted she brings along bodyguard Brandon (Colm Meaney) for extra safety. Meaney is the most famous actor in the film, and he is a perpetually decent one and ably rises above the material. Just do not get too attached – this modestly budgeted feature clearly could not afford Meaney for the whole adventure.

It is difficult to fairly judge the rest of the cast, because they are by-and-large not served by a script with depth. McIntosh seems capable, and benefits from a few individual moments of grief and trauma. Beyond that, it seems difficult to say for sure. When your only real narrative purpose is to be eaten, it is difficult to express much beyond fear.

It probably goes without saying that in these sorts of lowest-common-denominator thrillers, the rules of physics and biology do not typically apply. Anyone expecting the film to accurately reflect how sharks move and behave will be disappointed, as will anybody hoping the film will address the problem of decompression sickness in an aircraft lying at least 100 metres beneath the ocean’s surface.

Claudio Fäh directs the film with a solid sense of timing, and manages to fill out 90 minutes with a particularly restricted setting and story. Andy Gray’s musical score is generally effective, and a step up from the typical standard one finds at this end of the film industry.

It is difficult to praise No Way Up too enthusiastically, because it really is the very definition of mediocre film, but at the same time it must be noted that it is essentially fit for purpose. This is cinema as time filler: it gets in, broadly entertains an undemanding audience for 90 minutes, and then gets out. It seems unlikely many viewers will hate it, but I would not expect them to remember much of it afterwards. This is a film designed to be watched with one eye on your smartphone.