An R-rated superhero movie. Who woulda thunk it? Well, Deadpool did, in 2016. As did Watchmen in 2009. Hell, you can go all the way back to Marvel's crappy non-starter The Punisher (starring Dolph Lundgren!) in 1989. Nevertheless, taking one of Marvel's most popular characters and plunking him into an ultra-violent, potty-mouthed thriller is a milestone. And audiences were clearly receptive: Logan was an instant hit, even with 20th Century Fox going with an oblique-ish title instead of extending the X-Men brand.

Is it worth the hype? Well, let's say that its greatest achievement is that it tweaks our notions of what a mainstream superhero movie can be.

Set in 2029, Logan teases plenty of tantalizing back story: something happened at or to the Statue of Liberty; the world's mutants – the X-Men franchise's raison d'être – are all but extinct, with no new births since 2004; X-Men founder Charles Xavier did something terrible a few years earlier. These details are only touched upon: for director James Mangold, who wrote the story and co-penned the screenplay, they're either just facets of his world-building or a list of concepts for potential X-Men sequels. Logan doesn't even explain how Oklahoma City, of all places, might become a casino-choked Vegas rival within the next twelve years.

It's all a little intriguing and a little frustrating, kind of like the film itself.

This future Logan, a.k.a. Wolverine (Hugh Jackman), is an aging, broken drunk now driving limos for a living, while secretly caring for an addled, 90-year-old Charles Xavier (Patrick Stewart), who's hiding out in Mexico. It's an irresistible premise: to have the literally immortal Wolverine physically falling apart as Professor X, he of the most powerful brain in the world, suffers from a dangerous dementia.

The central plot, however, centers around rescuing a young Mexican orphan named Laura (Dafne Keen), whose mutant-like powers take a while to be explained. Naturally, evil scientists and villainous mercenaries are after her. With this shopworn storyline, Logan is less a superhero movie, and not quite the Western it alludes to, but really a sci fi pastiche of Children of Men, Looper, and Terminator 2.

Logan's got some cool concepts and Jackman and Stewart do great work. The violence is brutal and relentless, yet it's also muddled and oddly coy about the carnage. My biggest beef is that, at 2 hours and 17 minutes, the film is overlong by a good half hour. I do love how it breaks from the traditional superhero narrative, and I hope it allows for further deviations from the norm, but the exhausting Logan doesn't quite hit the high bar it sets for itself.