Chloë Grace Moretz plays Ohio teenager Cassie Sullivan, a normal high school student whose life revolves around her loving parents Oliver and Lisa (Ron Livingston and Maggie Siff), her doted-on younger brother Sam (Zackary Arthur) and the monstrous crush-from-afar she has on good-looking football player Ben Parish (Jurassic World’s Nick Robinson). Relocating to a refugee camp with Oliver and Sam, Cassie gets a shock when the army, led by Colonel Vosch (Liev Schreiber), show up and announce that the aliens can take human form (thereby saving a fortune on digital effects, which is just as well as most of the budget obviously went on the digital destruction early on). Soon afterwards, Sam is shipped off to a training facility (where he winds up drafted into a unit of children headed by Cassie’s former crush Ben, now nick-named Zombie), while Cassie witnesses a devastating incident that forces her to flee for her life into the woods. There she receives help from mysterious stranger Evan Walker (Alex Roe) – who just happens to be really, really good-looking – and the pair plot to rescue Sam from the army base. Director J Blakeson (who made taut British thriller The Disappearance Of Alice Creed) sets out his stall early with a shocking prologue (one that contributes to the film’s 15 certificate), thereby establishing a darkness of tone that, one key sequence aside, the rest of the film never quite lives up to. That said, Blakeson maintains a decent pace throughout and does a good job of balancing the two halves of the story once Ben becomes the focus of the action in the training camp. In addition, Roe does a decent job of selling his character despite being saddled with all the film’s worst lines, though the filmmakers hedge their bets by including an amusingly gratuitous sequence where he strips to the waist and scrubs his washboard abs in a convenient lake. As YA post-apocalypse franchises go, The 5th Wave has a lot more going for it than, say, the Divergent saga or The Maze Runner series, helped considerably by its likeable characters and its refreshingly uncomplicated plot. It also successfully incorporates elements from the two giants of the YA movie genre, Twilight (it has its Team Ben vs Team Evan love triangle all geared up and ready to go for the next movie) and The Hunger Games (with its inherent distrust of the ruling, adult forces), without ever feeling overly derivative. The film’s biggest problem is that its two central twists are so painfully obvious that you spend agonising chunks of the film waiting for the characters to catch up. This is particularly frustrating because, in both cases, the story would be much better served by earlier reveals. Still, despite a few wobbles in the teen romance department and the occasional spot of dodgy dialogue, this is ultimately an entertaining, decently paced slice of YA sci-fi that establishes a strong set-up and leaves you eagerly awaiting the next film.