In his last few minutes Reese mocks those around him and launches into a rendition of "Time is on my side" before expiring.
Soon afterwards people start dying in ways uncannily similar to Reese's victims so Hobbes starts digging into the footage from the documentary in case something from that might reveal clues to who his accomplice/copycat is.
No good will come of this.
This is a slightly clunky hybrid of the serial killer and supernatural genres with the titular fallen angel, Azazel, body hopping to engage in mayhem.
It's assembled from interesting ideas they keep dropping. At first it seems like Azazel speaks in tongues a lot then just stops. Then Azazel seems to have OCD briefly until they don't. At various points people say things like "do you believe in God" like it'll be deep but no it's just signposting this has biblical references. There's a little fiddling around with Police cover-up/corruption that again goes nowhere it's just an obfuscation technique to delay Denzel finding out helpful stuff so the plot can happen.
Embeth Davidtz has a really thin role as the daughter of another Detective who tangled with Azazel 30 years ago and paid the price but again refuses to tell him what happened to prolong the 'suspense'. Then a bunch of useful information is found in his old abandoned cabin in the woods having been left there years ago, which seems unlikely. Despite being set up as a Divinity and Theology academic perfectly positioned to be able to deliver exposition Davidtz is just there with no real part to play after Denzel finds the books and he just mansplains at her. At least she's not a shoehorned in romantic interest.
It has some fun bits with Azazel body hopping to initially confound and later frame Denzel and a great ending but the supporting stuff around that initially excellent core idea is kind of weak. Also James Gandolfini has a horrific moustache. 5/10 not really worth bothering with.