‘ Half Brothers’ is fun, but something’s rotten

There’s much to like about the road- trip comedy “Half Brothers.” It’s funny, smart, topical and even touching at times. But it’s hard to overcome the inescapable rot at its center.

As a boy in rural Mexico, Renato adored his engineer father, Flavio ( Juan Pablo Espinosa). Then t he economy c rashed. Flavio was forced to go to the States to try to support the family — and Renato and hi s mother never saw him again.

H e d i d n ’ t d i s a p p e a r ; h e became successful and remarried in America. Two and a half decades later, buttoned- up aviat i on executive Renato ( Lui s Gerardo Mendez) is preparing to wed his fiancee when he learns that his father i s terminally ill in Chicago.

He reluctantly goes to see Flavio for the first time in 25 years — and Renato l earns he has a half- brother. Wacky Asher ( Connor Del Rio) is a millennial “idea guy” who sports a headband and makes up for his lack of intelligence with positive energy. Flavio’s dying wish i s for his t wo sons to go on a long drive to the border to find clues he left that explain how they all got there.

There are funny references to stereotypes Americans and Mexicans have of one another ( such as a running gag about zip- lining, or when Asher tries to “comfort” Renato, newly arrived from Mexico: “You’re safe now”).

Del Rio is appropriately harmless and goofy. Mendez is a fine l eading man: Charming, multidimensional; this fi sh out of water is worldly and intelligent. We see him getting caught up in the ride.

The film i s also unapologeti cally set i n the world we currently live in. It effectively comments on t he humanit y often i g nored i n hi g hly poli t i c i z ed immigration debates. When we see detained families in foil blankets, it hits the target. There are direct references, such as when Asher blabbers, “I didn’t even want a wall,” but the comment a r y mostly c omes i n unspo - ken details.

It’s directed with Hollywood sheen by Luke Greenfield of the underrated “Let’s Be Cops.” That means e ve r y t h i n g ’s b r i g h t l y lighted, the score tells us what to expect, etc. But it also means the film moves at a good clip and has a sense of humor.

Unfortunately, it’s also built on a foundation of poorly packed landfill.

It’s no spoiler to say that the overarching point is for Renato t o understand why hi s f ather abandoned hi s f amily and t o forgive his absentee dad. Every cinematic clue tells us we are to sympathize with Flavio. And here, “Half Brothers” suffers a complete failure.

“Half Brothers” is a fun comedy with some heart and intell i gence, and i t embraces t opi c ali t y. Then, we’re f orce- f ed that poorly thought out string of excuses for terrible behavior. It’s like enjoying a fluffy pastry, then biting into something decomposing in the middle.