On paper, the justice system is meant to grant citizens a fair and just outcome in the event they are wronged by someone.

But what happens when the system fails to deliver? Is it then right to take matters into your own hands? Can vigilantism be a true form of justice?

These are the questions the Hong Kong police action flick “Detective vs Sleuths” tries to explore within its 101-minute runtime, and it largely leaves the audience to decide for themselves.

Directed by Wai Ka-Fai – whose impressive works range from action to comedy and romance – this film reunites him with lead actor Sean Lau Ching-Wan, with whom Wai had collaborated on 2007’s “Mad Detective”.

Wai and Lau are prolific figures in the HK entertainment scene, and “Mad Detective” – often named among the best films made that year – bears striking similarities to this 2022 release.

This places high expectations on the rather uninspiredly titled “Detective vs Sleuths” which, sadly, are not reached. Perhaps the absence of “Mad Detective” director Johnnie To could explain the shortfall this time around.

Here, Lau plays Jun Lee, a former police investigator who has been disgraced owing to his many mental issues. Not only does he see conspiracies everywhere, he also argues with the voices in his head – which often belong to the deceased.

And – spoiler alert – if you don’t think he sounds unstable enough, wait for the gunfight where he “shoots” at heavily armed suspects with just his fingers.

Despite having been kicked out of the HK police force, Jun continues following up on cold cases. Things take an ugly turn, however, when an elusive group who call themselves the “Chosen Sleuths” emerges.

These vigilantes target and murder the suspects of these unfinished cases, spray-painting cold-case numbers for the police to discover.

As clues emerge linking Jun to the group, it becomes increasingly apparent there might be more to the troubled investigator than initially presumed.

So, is “Detective vs Sleuths” any good? If you’re a fan of gunfights and crime, it’s definitely serviceable. But, apart from the action sequences and decent performances, the script is lacklustre and, for some reason, the events unfold quickly – too quickly.

Instead of letting the audience piece together the clues, the film seems more interested in rushing from one scene to the next. It’s clear Wai intended to create a psychological thriller, but the audience should still be given ample time to breathe and process what they have learnt along the protagonist’s journey.

“Show, don’t tell” is a commonly repeated adage in Screenwriting 101, but exposition is unfortunately aplenty in this instance. It would have been better for the events to play out on screen instead of merely being talked about. Why, Wai? Why?

In addition, with the story ploughing relentlessly towards its climax, viewers are given minimal time to delve into the characters’ motivations.

The idea of citizens taking justice into their own hands when the police and the courts fail them is an interesting one, but “Detective vs Sleuths” doesn’t go deeply into it. All the audience is told is that the Chosen Sleuths want revenge for wrongs committed against them – and that’s it.

Perhaps a scene or two exploring their motivations more deeply were left on the cutting-room floor… one can only speculate.

Despite its flaws, “Detective vs Sleuths” has its good points, with its dynamic action scenes and gunfights particularly well-executed.

Furthermore, there’s an ambiguous twist towards the end – one that can be thought of as either absurd or brilliant.

And when the Chosen Sleuths and the police run into each other inside a cramped apartment building, sweet, sweet chaos ensues as both sides draw their guns and exchange fire.

The bodies start piling up, and the audience gets to have a nervous chuckle as the mad Jun pursues his quarry with nothing but a finger gun for defence.

If you’re a fan of these glorious cinematic displays of violence, you’ll likely get your fix from watching this decent popcorn movie.

‘Detective vs Sleuths’ is playing in cinemas nationwide.