Theater

Hudes’ Iraqi vet trilogy ends with ‘Happiest Song’

“The Happiest Song Plays Last” is the kind of show in which people who look otherwise reasonable make big head-scratching decisions. And they don’t even seem to have consequences.

“Happiest Song” is the last entry in Quiara Alegría Hudes’ “Elliot trilogy” but the show’s accessible even if you haven’t seen the previous two. (For the record, they are 2006’s “Elliot, a Soldier’s Fugue” and last year’s Pulitzer-winning “Water by the Spoonful.”)

Set in January 2011 — an important date in the Middle East — the action goes back and forth between Jordan and America.

The trilogy’s unifying thread, an Iraq vet named Elliot (Armando Riesco), is shooting a movie in Jordan. Between takes he flirts with his co-star, Shar (Annapurna Sriram), and Skypes with his cousin, Yaz (Lauren Vélez), who’s back home in North Philly.

One thing Yaz doesn’t mention is the proposal from her friend Agustín to make her his baby mama. Considering he’s 20 years older, married and a drunk, this is an offer she should refuse — but inexplicably she agrees.

Maybe that’s because Agustín’s a good guitarist and she loves the Puerto Rican music he plays so well. Ruben Santiago-Hudson’s handsome production actually incorporates an original live score by Puerto Rican Grammy-winner Nelson González, who’s perched on a balcony overlooking Michael Carnahan’s salvaged-wood set.

Anyway, Yaz receives Agustín’s DNA, yet there’s no follow-up to her momentous choice.

The other fizzle is when Elliot drops by the Tahrir Square riots in Cairo. After much hand-wringing about danger and Google Maps, the trip is over and done. Dramatically, this is pancake-flat.

Hudes’ strongest asset is the diverse world her characters inhabit — something reflected in the Tony-nominated book she contributed to “In the Heights.” She also writes snappy, funny dialogue that mines cultural differences, as when Elliot describes shwarma as “basically an Arab burrito.”

But Hudes can slide into sentimentality and glibness, especially when mining the broken English of Elliot’s Iraqi-born fixer (Dariush Kashani). That scores laughs, but they feel cheap.