This is a strikingly atmospheric chapter, full of rich and complex imagery. At the same time it moves along quickly. The pacing is rapid and the proliferation of plot-bunnies is, in a word, prolific. There’s a lot going on, and it goes fast–though it could go even faster, as I’ll explain below.

In this iteration I think it’s clear that the noir detective is the viewpoint and the Doctor doesn’t appear until after Jack has established his identity and his function in the story. While the funky formatting hits my eye with chunks of undifferentiated text, with a little effort I can see how the paragraphs seem to want to be structured. For the most part I can follow the narrative.

The main thing I might suggest for revision is a bit of a step back, and some assessing of priorities, starting with the way the paragraphs are structured. There’s so much going on, so many details, such a heaping on of actions and reactions, descriptions, characterizations, and general plot-chewiness, that sometimes it’s hard to navigate.

First I’d recommend shortening paragraphs, teasing out viewpoints and angles and general what-happens-here, and giving each its own space. That way, it’s easier to follow what’s going on, but the prose will keep its overall lushness.

Here for example, at the very beginning, we see this:

It was only a matter of time. The identity of the “old-fashioned detective” had been his most successful, but most desperate disguise yet. It was a symbol of justice he had carefully crafted to try and prove that the world wasn’t lost quite yet, that innocence could still be protected, that life didn’t have to end with regret, and that even Black Jack could become one of the “good guys.” That symbol’s name is Private Detective John Stack. Tonight, however, that symbol is dying, for night has fallen in the Leviathan and with it came a monster.

There’s so much packed into this space. We learn that he has basically an avatar, the detective. Apparently he calls himself Black Jack. But then he has another name. And he’s dying. Or his avatar is. And it’s night somewhere called the Leviathan, and there’s a monster, but Leviathan is a monster, so are they the same thing? Or are they different?

What happens here is that we get one piece of information, then another that may be vaguely contradictory but is probably identical to it, but we can’t be sure before we move on to the next pair of is it/isn’t it. Some of this is probably intentional, because the universe Jack is operating in has that kind of recursive ambiguity to it. But the prose isn’t quite in control of itself yet, and the piling on of details within a single paragraph has the effect of jumbling them together.

Breaking them up will help. So will polishing for a little more clarity.

One way to do this is to prune the imagery. For example:

The unlit towers of the Old Downtown rise like skyscraping gravestones into the winter sky above.

There’s a whole heap of metaphors here: towers, skyscraping, gravestones. They rise, they’re in the sky, the sky is above.

Pruning just a couple of words removes redundancy without losing the sense: The unlit towers of the Old Downtown rise like gravestones into the winter sky.

Same strong imagery, clearer meaning. A similar pruning pass through the whole chapter will bring out the essentials, keep the atmosphere, and make the rapid pacing even more effective.

Watch for repetitive words and phrases, too. For example the Doctor purrs repeatedly and sometimes confusingly. She is Cat, yes? Which explains why she does this. But the connection could be clearer. It’s like Black Jack/John Stack and Leviathan/monster: the connection isn’t quite solid, and the proliferation of words and images makes it hard to catch the meaning.

And finally, in action scenes, it’s best in general to to keep the focus on a small number of very specific things that happen. If the scene goes on too long, it starts to lose tension, and the more so if it’s written slow—with long sentences and subordinate clauses.

In a rush of movement the gambler lunges forward and buries his dagger inches deep into the wooden door before he realizes the intruder has swiftly dodged to one side. In the flash of silence before the chaos begins, Stack’s lips are suddenly curled into a sadistic grin. After hearing his name for the first time in nearly a decade, Black Jack smiles at the world once more.
Try reading this aloud and see how slowly it moves. It means to be fast, it means to be strong. It wants to hit hard and move on quickly.

Shorter sentences, stronger constructions, more active phrases, will make this happen. Less repetition, more focus. More punch and pow.

The gambler lunges forward and buries his dagger in the door, too late. The intruder has dodged aside.

(new action, new viewpoint, new paragraph) In the flash of silence before chaos begins, Stack’s lips curl in a sadistic grin. For the first time in nearly a decade, Black Jack smiles at the world.

In short, and in sum: Definitely you don’t want to lose your wonderful atmosphere, but tightening up the prose and clarifying its meaning will make it work even better.