Brendan Gleeson started out as a teacher. In Ireland that usually comes with some job security, if not exactly stellar wages, but the stability for a young family must have had its attractions.

But then at 34 years of age and with a few acting stints under his belt in the early 1980s with Dublin’s celebrated Passion Machine Theatre Company, Gleeson decided to commit to the unpredictable life of a film actor. 

It was a wise move. Irish fans have since come to know him for his unforgettable turn as a crime land boss in "The General," and for equally celebrated films like "Braveheart," "Breakfast on Pluto" and "The Guard."

But this year is becoming the biggest of Gleeson’s film career to date thanks to his acclaimed performance as a parish priest in the forthcoming "Calvary" (written by John McDonagh, the writer of "The Guard"). 

This week, though, Gleeson plays a military general in "Edge of Tomorrow," a surprisingly smart new Tom Cruise sci-fi thriller that’s one part "Groundhog Day" and one part "War of the Worlds."

The film throws us in at the deep end. An alien species has invaded the planet, and their superior technology and tactics make them look completely undefeatable. It’s one of the strengths of the new film that we see very little of the new alien race at first.

Gleeson plays General Brigham, the man tasked with the unenviable job of preparing a massive ground invasion of France with tens of thousands of foot soldiers to counter the aliens. Brigham knows he will have to carry the can with the bereaved relatives if the operation fails.

That’s why he invites Major William Cage (Cruise) on board. Cage is a major mostly in the sense that he’s a major player. With his civilian background as a top player in an advertising agency, General Brigham wants him aboard to blunt any bad press that might come his way once the invasion is launched.

But Cage has other ideas. As we soon see, he’s no one’s idea of a hero. In fact he resorts to a blackmail attempt to prevent his participation in the ground assault. 

For his pains he gets arrested by Brigham, then demoted and sent out and that’s where his troubles begin – over and over again, as it turns out.

Edge of Tomorrow is the best thriller Cruise has starred in for over a decade because the script is smarter than usual, and director Doug Liman has the sense to let this character-driven tale carry us forward. Liman sets up the action and trusts us enough to figure out what the stakes are, rather than brow beating us as is usual with big budget fare. 

Warner Bros have clearly broken the bank to produce this film. The sets are gigantic, the battles are mind-blowingly tense and the aliens, once we finally see them, are creepy and terrifyingly lethal.

Cage screams when he sees what the aliens can do to a troop carrier, and he screams louder when he sees what they can do to unfortunate soldiers. But Cage gets lucky.

After being attacked he finds his DNA has somehow been shared with the alien race, permitting him to fight like they do, using time travel to repeat a battle over and over until he has totally destroyed his foes.

It sounds crazy, but if you’re forced to live the same day over and over again, getting killed again and waking up to do it all over, you start to figure out how best to make your moves. That’s how the aliens win every battle, but it’s the chink in their armor that could defeat them too.

When Cage takes this realization to Brigham, Gleeson’s seen-it-all general gives him one of his already world famous, "get up the yard" stares. It helps that Cage had brought backup in the shape of Rita (Emily Blunt), the soldier that even her own battalion call the Full Metal Bitch. 

Rita is a particularly interesting female summer super hero because she stands on her own, seeks no one’s approval and doesn’t need some macho twit to fly in and tame her by the final reel. 

Instead of being a helpless doormat she’s her own woman, powerfully so, and she’s also the best soldier the unit has ever seen. You’ll want to cheer her on.

Unfortunately she’s also dead, or soon will be, over and over again just like Cage until she can figure out how to use time travel in the same lethal way the aliens do. Rita doesn’t have time to convince Brigham that he’s making the biggest mistake of his or anyone else’s life and leading the world toward a total disaster, so instead she lets Cage do the talking, then busts them out of the trap that’s about to spring. 

There isn’t a lot of chemistry between Cruise and Blunt, which is inevitable given the tense circumstances. Instead there’s something even more interesting: complete equality. Both live and die together, hundreds of times, and in the process they get to know each other in a way few people ever will.

There’s something unusually moving about the relationship between this pair. Although they’re temporarily immortal, their timelines don’t match, so Cage gets ahead of Rita and knows more about her from the start. 

When he falls for her – and he literally falls for her – it’s torture because he has to watch the person he loves die repeatedly, and worse – he has to reintroduce himself over and over.

This is heavy stuff for a summer popcorn guzzler, which is why you’re probably going to forget to guzzle the popcorn. "Edge of Tomorrow" has action, epic sets, amazing sci-fi technology, terrifying aliens and enough explosions to last you until "Guardians of the Galaxy" is released. 

But it also has a rare degree of intelligence which makes it infinitely more satisfying. By sticking with Major Cage, he grows up from being a selfish, cowardly cynic to a principled (and loving) man of action, we witness Cruise remembering to do what he used to do best: be a movie star.

Gleeson doesn’t need the practically guaranteed success of "Edge of Tomorrow"  in order to make noise this year. 

His for-the-ages performances as a priest under a death threat in "Calvary" has already made this the year his name will appear on multiple award nominations. But it doesn’t hurt to make some serious bank along the way as both he and his rapidly rising son Domhnall (who has been cast in the new "Star Wars" film) are both now doing. 

It’s been a good summer already for big budget action films, and with Irish stars like Michael Fassbender, Liam Neeson and both Gleesons making the cut for the top films, it looks like the world’s top action heroes are likely to have Irish accents for years to come.

Brendan Gleeson in Edge of Tomorrow.