Let’s get that elephant out of the room first off and say yes, Filth more than resembles Danny Boyle’s Trainspotting. Both films are based on novels by Scottish author Irvine Welsh, both feature snappy editing and a carefully curated soundtrack, both rely heavily on voiceover, and finally, both feature a nihilistic sociopath who couldn’t give a fuck about redemption. The difference is that Filth seeks to eventually gain your sympathies, tricking you to care about a character who’s just dragged you through the gutter of human depravity for the last 90 minutes, only to offer up an absolution that, while attempting to be dark and edgy, is just flat and unconvincing.
Bruce Robertson (McAvoy) is an Edinburgh policeman spiraling into insanity while also gunning for a promotion to detective inspector. All that's standing in his way are his five co-workers, also up for the job. Through his game of shame, scandal, and blackmail, the film follows his attempts to secure that position at the expense of his fellow cops. There’s also the murder of a Japanese student by a handful of chavs that forms the overarching narrative, but mostly it’s Bruce behaving badly, asking random women for blow jobs, masturbating at inappropriate times, setting up his colleagues in diabolical ways, disregarding police protocol, and, well, you get the idea.
It’s not like everyone involved isn’t giving their all. McAvoy works overtime to breathe life into the main character, and the film has just about every contemporary British character actor working today popping in for one scene or another. Yet, the film seems past its expiration date, trying too hard to be vulgar and grotesque and ending up coming off as puerile and half-baked. To its detriment, Filth too often pulls its punches, and if you’re striving for pitch black, that is most definitely a cardinal sin.