It's 2029 and mutants are an endangered species, with no new mutants being born. Logan (Hugh Jackman) is making a living as a chauffeur in El Paso, Texas, keeping his head down and nursemaiding a 90-year-old Charles Xavier (Patrick Stewart).
Both men are well-past their prime, sickly, and losing control of the abilities that made them such key members of The X-Men.
Charles is battling dementia, meaning that his mental powers go out of control when he fails to take his medicine and has a seizure, while Logan finds his healing power is not what it was.
The world isn't exactly post-apocalyptic, it's just bleak and run down. Like the film's protagonist.
Thrust into this mix is a young mutant, Laura (Dafne Keen), whose talents seem very similar to Logan's.
And she is being pursued by the paramilitary Reavers, led by Donald Pierce (Boyd Holbrook), the head of security for biotech company Alkali-Transigen.
It turns out that Transigen has been creating clones from the DNA of known mutants, to be trained as soldiers, only the children had no interest in fighting.
One of the nurses at the company's research facility managed to spirit Laura away before any further harm could be done to her.
But Transigen wants its "property" back.
Beyond just the strong language and graphic violence, Logan is unlike the majority of mainstream comic book superhero movies.
Director James Mangold has a singular vision for this unique take on the genre. There are no superhero costumes, everything is very down-and-dirty, tired and almost drained of colour.
The world isn't going out with a bang, it's just running out of steam... unless a new generation can be found to get things going again.
There is, as you would expect, plenty of action in Logan, and some grand special effects sequences, but this is a more contemplative and cerebral movie, examining such themes as the power of mythology and labels, for good or ill; the consequences of violence; the ravages of time.
It's a road movie crossed with a contemporary Western, set against a desert backdrop, stirring up echoes of Unforgiven, Shane (which is acknowledged in the film), Badlands, Mad Max (particularly Fury Road and Beyond Thunderdome) and others.
Interwoven with this is the family dynamic of Logan, his "daughter", Laura, and his father(figure) Charles, coming to terms with the reality of their situation, their places in this new world, and their destinies.
Given the size of these personalities, the villains of the piece (Pierce and his boss, evil scientist Rice, played by Richard E Grant) play a distant second fiddle to the protagonists, but that doesn't really matter.
It's all about closing a major chapter in the cinematic world of The X-Men in the most visually elegiac and lyrical way possible.
Logan is a live-action encapsulation of a Johnny Cash song (which is why his The Man Comes Around over the end credits works so well).
James Howlett, aka Logan, isn't the Wolverine we know from the earlier X-Men films, age is finally catching up with him and he no longer feels indestructible, but this gives Hugh Jackman the opportunity to give the character everything he's got.
This is a magnificent, and tonally perfect, heart-breaking yet optimistic, send-off for the superhero that he has played since 2000, and will - forever - be associated with him.