I love the feel of this, and your style of rendering. But I was puzzled by the bowler hats before you described the story, wasn't quite sure what they were. And even after, I think they are a bit odd, with the cigar just hanging there underneath, with no face or anything else.
Take this with a grain of salt, because I'm no expert, but I'm thinking of movies or posters I've seen, where there is a villain in the dark and you can only see a silhouette with some rim light, and a glowing cigarette, and maybe the whites of their eyes. Maybe if you just had one of them and did something similar. The shapes of the jacket could be the background, interacting with other elements. I like the smoke in the background, maybe you could have it also come forward and obscure the edges of some foreground elements.
The main point is I think the elements need to vary in size more, as has been said. Otherwise It is a nice image and I love the way you draw and your texturing. I love the hand lettering also.