Kill List is the kind of film whose full impact doesn’t hit you until after you had a chance to reel your mind in from the incredibly intense ending. Like Down Terrace, director Ben Wheatley’s last film, it follows the exploits of people living outside the law while moving in less expected directions, but has more of an emphasis on the physical and psychological pitfalls of their morally ambiguous lifestyles and the horrors, conventional and otherwise, it leads to.

Feeling the strain of a floundering economy, Jay (Neil Maskell) and Shel’s (MyAnna Buring) marriage is spiraling downward more every day as the emotional outbursts become increasingly hostile. After an explosion at a dinner party, the marriage seems to be on its last leg when Jay decides to take up a new job with his friend Gal (Michael Smiley) to relieve some of the strain. Of course, being a hit man brings on its own stress, and taking on the new contract – aka the “kill list” – begins to take a turn for the sinister as the hirer’s agenda and antics become more and more bizarre.

While the men whittling down their list is what moves the action forward, the focus is really on the spell cast over the audience and the characters. Early on in the film, we see Fiona (Emma Fryer), Gal’s girlfriend, put a symbol of sorts onto a wall fixture in Jay and Shel’s home and from then on Jay’s psyche starts to crumble rapidly, causing him to become more reckless and violent – a scary thing considering he kills people for a living. Luckily, Gal is there, acting as a mentor of sorts, to pull him back in, even if it is only for a few moments at a time. Kill List isn’t a film with big scares or loud noises; it’s one that strives to be unsettling, and it succeeds in spades.

The religious parallel functions quite effortlessly alongside the psychological aspects, as Jay’s susceptibility to “bad mojo” is increased as he renounces belief in a higher power. Not only does his job require him to throw moral convictions out the window but, as he explains to a fellow diner at his hotel’s restaurant who decides to play Christian tunes during dinner, he doesn’t believe God exists. Although third act revelations play into the internal conflict, Jay really begins his descent into religious turmoil when he assassinates a priest with little remorse.

Kill List is a film that warrants a second viewing, if only to see how seemingly unrelated incidents connect in hindsight. On a first watch, however, Wheatley’s hit man horror is an atmospheric delight, boasting incredibly intense performances by Maskell and Smiley, and a doozy of an ending that will unhinge even the most hardened of genre fans.