A B-movie for sure -- the storyline is contrived, the dialog is superficial, and the acting is wooden. So my rating of 5/10 is probably generous. Nevertheless, I thought it was watchable and it fitted the purpose of having something to look at while I was exercising. Lead actress Elsa Patacky is front and center throughout this movie, playing US Army captain JJ Collins, who as soon as she is assigned to the remote marine base SBX-1 has to fight off terrorists who want to nuke 16 cities and destroy America. Somehow there's lots of money involved. Luke Bracey, as the smarmy leader of the enemies, has an easy way of delivering lines even if those lines are laughably conventional. And, Patacky's husband Chris Hemsworth (who's the executive producer -- what a coincidence) has a little cameo role that's completely meaningless but still pretty fun.
Almost right off the bat, Patacky gets down to action gear where we can enjoy looking at her very well muscled shoulders and arms (and that's kind of the main interest of the movie -- they really are nice to look at). There's lots of hand-to-hand combat and a fairly high body count, with the hero(ine) taking and dishing out lots of punishment and displaying superhuman stamina, but I'd be hard pressed to think of any original twist on anything that happened here. The idea that the US missile defence system depends on a single little remote ocean base that seems about as hard to knock over as a candy store is pretty implausible.
It feels like a B-grade version of Die Hard.