“BEIRUT”

** 1/2

(R, 1:49)

“Beirut” is a spy story. But what’s its mission?

Set on the eve of Israel’s 1982 invasion of Lebanon, it’s a complicated story of Americans, Israelis and competing terrorist groups. There’s a mess of double-crosses, disloyalties and secret agendas.

But the movie’s just as murky.

It starts in ‘72, with an unconvincingly de-aged Jon Hamm showing up as Mason Skiles, the State Department’s top man in Beirut. A terrorist attack strikes his family and shatters his friendships; Hamm flies home and promptly crawls into a bottle.

Flash-forward a decade, and suddenly the CIA wants Stiles back in Lebanon, in a hurry. One of their spies is missing. And they think Stiles may be the only person who can find him, for two good reasons.

One, he knows the victim. And two, he may know the kidnappers.

“Beirut” isn’t a stupid movie. Its director, Brad Anderson, made a couple of dark little pictures, including “The Machinist” and “Transsiberian.” Its writer, Tony Gilroy, wrote the “Bourne” movies and “Rogue One.”

(He also wrote “The Great Wall,” but we’ll try and forget that.)

So, no, this isn’t some adrenaline-pumped spy picture, with the hero racing through markets on a motorcycle while merchants shake their fists, or grimly running at the camera in slow-motion while things explode behind him.

Gilroy already wrote all those movies.

But it’s not exactly a clever, character-driven, John le Carré story either.

Things unfold, but the characters never deepen. We know as much about Skiles at the end of the movie as we did at the beginning — he’s a drunk, and depressed, and a great bluffer. Somehow we know even less about the other characters than we thought we did at the start.

The movie, although shot in Morocco, still feels painfully authentic at times — you can almost smell the fresh gunpowder, and old garbage. And Rosamund Pike gets a few sharp lines as “the skirt,” a minder assigned Skiles because the government assumes her prettiness will distract him.

They’ve underestimated her.

But the people behind “Beirut” have overestimated themselves. Its characters are thin and its biggest twist is far too obvious. The story feels rushed, with holes where the big moments should be, the Post-It notes still attached: Serious Scene to Come Here.

Pike is terrific, and Hamm has a credibly bleary, weary look. The movie’s ambitions are worthy. But it rarely turns its action into real excitement, or moves past cynicism into insight.

It’s the spy movie that leaves us in the cold.