This late period in Clint Eastwood’s career is a source of pretty endless fascination for me. At a time when most filmmakers have either called it a day, or are spoiling their reputation with increasingly disappointing movies, Eastwood has proved, conclusively, that he’s still capable of greatness as he nears 80. The run that started with Million Dollar Baby shows no signs of abating, and this slew of movies are among the best of his career.

The news of his latest, Gran Torino, arrived in a flurry of excited whispers that it could be the long-rumoured sixth Dirty Harry film. Certainly, the one-sheet poster, a moody black and white image of Eastwood, cradling a shotgun, leaning against the Gran Torino (Harry’s car of choice), certainly suggested we might be in for some kind of Harry-in-retirement story.

But as it turns out, although Gran Torino isn’t the fabled sixth Harry movie instead it’s a movie that addresses aspects of Eastwood’s own mythology in a way you might not immediately suspect. Eastwood (who also directs) plays Walt Kowalski, a recently widowed Korean war veteran. He’s also endemically racist, which doesn’t help the fact his Detroit neighbourhood seems now to be totally populated by immigrants, who he unapologetically refers to as “gooks”, “Chinks” and “spooks”. Kowalski is a man from a different age, who’s resolutely refused to change to suit our more politically correct times. He’s also frankly terrifying when riled, revving up some of Harry’s old charm by making lines like “Get off my lawn,” sound as threatening as “Make my day.”

Of course, Gran Torino focuses on the gradual humanisation of Kowalski, and offers redemption of a kind for this fairly unpleasant man. His Hmong neighbours are caught up in gang war – first with the Mexicans, then with their own people – and Kowalski finds himself drawn slowly into first helping them defend themselves and then befriending them.

But it’s what Gran Torino says about Eastwood’s own mythology that I find pretty fascinating. Principally, I’m struck by how much it feels like a comment on a classic Eastwood staple, his character as some kind of vehicle for vengeance, that’s there in the Leone movies, and through the Revisionist westerns like High Planes Drifter, Pale Rider and Unforgiven. I find Unforgiven, perhaps, the clearest reference point here, certainly the idea of a man forced by circumstance to resume his violent ways. But there’s a definite sense of Eastwood inverting this, particularly in the third act, and by extension blindsiding the audience’s expectations of what’s to come. It’s also strangely playful; the sight of Kowalski growling at his inappropriately-dressed grandchildren during his wife’s funeral service is both funny and again a sly subversion on the intolerance of the conventional Eastwood character.

So what does Gran Torino say about Eastwood at 78? Most obviously, that he’s still a capable man of action (interestingly enough, Gene Hackman and Paul Newman both passed on this before Eastwood signed on). But perhaps most intriguingly, how he’s prepared to revisit and subvert his own tremendous mythology.

We can take it as a given, of course, that the film is excellent.

Gran Torino opens in the UK on February 20. You can watch the trailer here.