“Edge of Tomorrow” opens Friday at Point, Eastgate, Star Cinema and Sundance. PG-13, 1:53, three stars out of four.

If you like Tom Cruise, then you will like “Edge of Tomorrow,” and if you don’t like Tom Cruise, then you will like it even more. Cruise gets shot, smashed, drowned, run over by a truck, burned with acid, and ripped apart by whirling calamari aliens over and over again. Somewhere, Brooke Shields is smiling.

Cruise plays Major Cage, an oily PR guy who has been all over cable news selling the human race on a war against the vicious alien Mimics, who seem to be able to anticipate human armies’ every move. Underneath the made-for-TV bravado, Cage is a flat-out coward and sneak. “I do this, so I don’t have to do that,” he explains to a general (Brendan Gleeson), pointing to a tactical map. It’s Cruise’s best acting in a while, steering into the unctuous Mr. Perfect persona he can sometimes project.

The general has other plans, and has him arrested and sent to the front in France. The massive operation is supposed to be humanity’s final victory over the Mimics, but it’s a slaughter, and the film captures the terror and chaos of Cage being caught on a massive battlefield, death and destruction all around, unable to figure out how his guns work.

He dies, of course, while fighting one of the larger Mimics. And then he wakes up, back on base, a few hours before the attack is supposed to start. He goes through the same events, lasts a little longer in combat, dies again. Back to square one. Eventually, he comes across Rita (Emily Blunt) a supersoldier who has become the face of the human resistance. “Come find me when you wake up,” she tells him, just before he dies yet again.

There’s a reason why Cage keeps dying and rebooting, and lots of exposition about the nature of the aliens, but frankly, how much fun is that? What’s fun is watching director Doug Liman (“The Bourne Identity”) and screenwriter Christopher McQuarrie (“Jack Reacher”) put Cruise through the wringer, each death a sudden punch line to a joke. And the more times he goes through his final day, the better he gets at fighting Mimics, until he’s a supersoldier like Rita, ready to go hunting for the alien “mothership.” “Edge of Tomorrow” has been compared to “Groundhog Day,” sure, but to me it’s the sci-fi equivalent of Malcolm Gladwell’s “10,000 hours” theory. Just put in the time getting killed by aliens, and you’ll be a hero someday.

One thing I really enjoyed about “Edge of Tomorrow,” in a summer blockbuster season where every action scene is treated as ponderous and world-shaking, is that the action in this film, although very well-staged, is happily pointless. No matter how skilled Cage becomes, how many aliens he offs, he still gets killed. The frenetic action becomes kind of a backdrop to a more interesting story about fate, not to mention some nice chemistry between Cruise and Blunt.

I got a little less interested in “Edge of Tomorrow” as it moved towards a more conventional climax, and Cage’s endless rebooting became replaced with a different sort of invulnerability, that of movie-star Tom Cruise. It’s understandable, given that the film is following Cage’s arc from coward to hero. But I wouldn’t have minded seeing Cruise hit by a truck just one more time.