There's real danger and suspense in the first half, which may remind viewers of Mark Wahlberg in "Lone Survivor." Having hired new Afghan interpreter Ahmed (Dar Salim), Army Sgt. John (Jake Gyllenhaal) has just begun to let him into his circle when the Taliban ambush them. Stranded in the middle of nowhere with no vehicle, they must try to get to safety while deep in enemy territory.

Under the direction of co-writer Guy Ritchie, these scenes are tense and understated. The men don't know if they can trust people they encounter — they're not even sure they trust each other — but each has to rely on the other as the perils of their several-day journey pile up.

I don't want to spoil what happens but their relationship grows by degrees, giving both men the opportunity to demonstrate heroism: Ahmed while they're on the run in Afghanistan and John when, back in the U.S., he learns his colleague is in jeopardy.

Gyllenhaal is the big name in "Covenant" and he's fine as the intense, passionate John, but the discovery here is Salim. The Iraqi Danish actor, probably best known for several episodes of "Game of Thrones," is an intelligent, soulful presence. Much of the movie comes from John's perspective, so Ahmed is meant to be mysterious, but Salim's quiet directness — despite multiple life-and-death situations, he never raises his voice, as if to remind us that danger lurks everywhere — keeps us a step or two ahead. Even if John is unsure of his colleague, we know he's a good guy and that he and his family desperately need the trip to America that's been promised for a job well done.

Ritchie — who is fond of movies in which one Cockney guy tells a joke while sticking a bullet in the eye of another Cockney guy ("Lock, Stock and Two Smoking Barrels," "The Gentlemen") — has never been the subtlest director. But, especially in the first half of "Covenant," he lets the charged material speak for itself.

Instead of layering on jump cuts, crazy camera angles and jokey subtitles like he usually does, he keeps things calm. Ritchie lets the action unfold swiftly and clearly. Even the musical choices are subtle, with Vietnam-era songs by the Hollies and America reminding us of another guerrilla war that the U.S. got stuck in.

The second half of "Covenant" is less successful. That's when Ritchie mirrors John's hot temper by indulging in gonzo editing and filming that make us doubt his storytelling (although not based on any specific incidents, "Covenant" was inspired by the lives of many Afghan interpreters/soldiers).

Ritchie rights the ship for the ending, but those frenetic middle scenes also throw off the movie, which is weighted equally between the two leading characters, even if one of them is played by an Oscar-nominated star.

"Covenant" does a terrific job of helping us understand how difficult it is for John to trust an ally who looks and sounds exactly like the people John is fighting against. But why doesn't the movie also acknowledge how tough it is for Salim to trust mercurial, hair-trigger John?

'The Covenant'