Clint Eastwood will be 88 in May. This is the director's 36th film. I mention these facts up front because The 15:17 to Paris makes one thing abundantly clear: It's not at all clear the filmmaker still knows what he's doing.

But, Rick, you gave the movie four stars. And I'd have added a question mark if I could. I'm going out on a critical limb in deference to the double Oscar winner's accomplishments, wagering that this stunningly dull work is stunningly dull by design. That he isn't in the early stages of dementia but at the peak of his powers, experimenting with radical new approaches to narrative. That Eastwood has gone avant-garde.

At first glance, his latest appears to be in the vein of recent work. American Sniper and Sully celebrate everyday men who rise to extraordinary occasions. The 15:17 to Paris does likewise, recounting the true story of three friends who made headlines on August 21, 2015, by subduing an ISIS-inspired terrorist before he could massacre everyone on board Thalys train 9364.

Ayoub El-Khazzani had zero reason to believe he wouldn't succeed that day. What chance would passengers trapped inside a speeding steel tube have against an asshole armed with an AK-47, 9mm automatic Luger, box cutter, canister of gasoline, nine loaded magazines and nearly 300 rounds of ammunition? That train had 554 passengers. You do the math.

Here's where things get all Jean-Luc Godard. Eastwood originally intended to cast actors to play Spencer Stone, Alek Skarlatos and Anthony Sadler. His choices were announced in the trades last June. Then he decided to go in a different direction.

The filmmaker reconceived the project with the childhood friends playing themselves. He structured it such that 99 percent of the film is devoted to chronicling their Christian upbringing, military training and serial selfie-taking while on European vacation before the fateful train ride.

Make no mistake, all of that — especially the childhood stuff — is excruciatingly boring. First-time screenwriter Dorothy Blyskal displays a flair for transforming the merely banal into the synapse-slaughteringly tedious. As for the nonactors, they elevate not acting to a not-art form. Even the climactic clash, finished in minutes, is anticlimactic. So what's the deal?

I posit that Eastwood could be attempting something truly revolutionary. In "Dream Song 14," the poet John Berryman wrote, "Life, friends, is boring." My theory is that the director made an artistic choice to roll the cameras and let virtually every minute of this movie stand for life by screaming, This isn't interesting!

Famous for his unfussy style, Eastwood shot even fewer takes this time than usual — just one, in fact, of the picture's key sequence. The result is a stilted, super-snoozy monument to uneventfulness. The movie's creators take a pass on character development completely. Ironically, it's the ultimate anti-action film.

But what Eastwood may be embracing is the uneventfulness of everyday life. Like all art that employs negative space, The 15:17 to Paris is really about what the audience doesn't see: in this case, the unthinkable horror El-Khazzani would have unleashed if a handful of ordinary people hadn't done what they did. It's as if Eastwood is saying, "Look, this may not be terribly dramatic, but neither is life most of the time. On that August day, life got the better of death. Let's celebrate that with a big fat serving of reality in all its glorious ho-humness."

Unless I'm wrong. In which case, this is merely the most stunningly dull movie the man has ever made.