If you know anything about South Korean cinema, you will be aware they have a penchant, for quality crime action thrillers.
"Nocturnal" satisfies the crime action side of the equation but falls a little short, on the thriller aspect of this tale. The story, at its climax, ultimately feels a little predictable and underwhelming.
That's not to say this isn't an inherently watchable production. The gritty, no holds barred crime aspect of this film is done exceedingly well. There are dark, well rendered characterisations, who have a fatalistic view of life and its hardships. Equally, the extremely violent, street clashes between a protagonist, out for revenge and mafia style, street thugs is frenetic and enthralling.
In summary, not quite the thrilling tale I had hoped for but what is offered, is extremely well done. Suffice to say, if you like this kind of thing, "Nocturnal" is well worth a look.