It must be a fine balance to write a screenplay that consistently wrong-foots the audience, makes them smile occasionally while delivering a fairly grim and creepy story, and ensures that it all makes sense too. Nick Simon, who directs and co-writes achieves this very nicely. There's an irresistible grim strand of humour running through this, although the main character Cole has little to be cheerful about. Mark Kelly is very good as the flawed central character, fighting several of his own personal demons, as well as the manipulations of those around him. Even Oz Perkins as the the unpleasant Henry Sharpe has a dry line in humour.
That the twists and turns pay off is a bonus - it isn't always the case, and while there's nothing wrong with open-ended stories, it's good to have things tied up here. Morte than that I won't reveal.
As a chiller about a put-upon industrial cleaner, Removal works very well indeed. My score is 9 out of 10.