Pretty amoral though with respect to Trevor's wife but I guess it was meant to be. That's probably why he left the life....
So more an anti hero spaghetti western.
I'm no film critic but I think Riz Ahmed really brings the role to life, portraying a very calm and calculated protagonist, losing his steely demeanour only under extreme stress and even then only for brief moments. His acting is spot on with micro expressions that offer more insight into the character than he has to say. He absolutely made the movie for me. I don't think it would have been half as good without him involved.
That said, there are supporting cast members that did my nut. Even if you're exporting the movie, you don't have to exaggerate Britishisms quite so much for them to be understood.
All things considered, this is a decent movie. 3.5 stars for the project, 4.5 for Riz Ahmed.