It’s weird because this kind of movie has worked before, and the actors leading the effort in “I Don’t Understand You” have been funny and engaging before, but so little goes right with this one that it’s honestly astonishing. A lost-in-translation cringe comedy with relationship aspirations and bloody sensibilities, the film has a shallow bench of ideas and jokes, running the few it has into the ground right alongside its characters.
“I Don’t Understand You” opens with a couple, Dom (Nick Kroll) and Cole (Andrew Rannells), making an adoption video for a prospective baby momma, Candace (Amanda Seyfried). Conversation tidbits reveal that this isn’t their first attempt at parenthood, and the stress of the drawn-out adoption process seems to have eroded the foundation of their relationship a bit. U.S.-based, the pair goes to Italy for their tenth anniversary, hoping to take their minds off the stress of the adoption process and also to reignite the spark of their marriage.  
The couple stays in Rome, yet reluctantly agrees to travel deep into the country one evening at the insistence of a family friend who arranges a special, private meal for them. Car trouble strands Dom and Cole, however, and they are forced to embark on a journey through the countryside without the help of Google Translate or any other technological assistance (the script finds a clever way to separate both men from their phones). What starts as a simple misunderstanding with a few locals devolves into accidental death/murder, with the couple fighting not only for their lives, but for their marriage and future family.
The movie plays its primary joke out before it is through the first act, with Cole and Dom fumbling through Italian conversations without any context or understanding, finding only slight variations on the same theme. The plot develops, and nasty stuff happens due to the poor communication, leading to a bloody cascade of foibles and follies a la “Tucker and Dale vs Evil.” Yet while that movie worked because the leads were lovable and the dead-meat victims weren’t, “I Don’t Understand You” curiously inverts the formula.
Dom is a pushover, creating a dynamic in his relationship with Cole that sees his partner take a back seat to whatever immediate intrusion makes Dom uncomfortable. Cole acts out as a result, creating a sometimes toxic dynamic that both men are understandably nervous about in light of their potential fatherhood on the horizon. And while this doesn’t make them terrible people by any stretch of the imagination, they get caught up in some awful shit throughout the course of this picture, and neither conduct themselves well during the ordeal(s).
Worse still, their “victims” are kind, reasonable people whose only sin is falling into the orbit of this reactive, panicky, morally dubious American couple. As things go sideways and the bodies/blood proliferate, it can be hard to know who/what to root for, here. And while the action is staged well and sold enthusiastically by Kroll and Rannells, it becomes harder and harder for a viewer to get on board and have fun with this thing.
Co-directors David Joseph Craig and Brian Crano also co-wrote the script, and any troubles the story suffers in tone and style don’t leak into its technical presentation. The movie makes terrific use of the Italian cityscapes and countryside settings, giving the story a legitimate sense of place and atmosphere throughout every twist and turn. The action is well staged, and Craig/Crano position the secondary characters well around the leads to complement Dom and Cole’s increasing desperation.
It just never clicks, and all the good acting, great lighting, and clever set design can’t plug the holes that the script’s basic conceit pokes into this thing. “I Don’t Understand You” is played for laughs, yet the jokes aren’t that funny, and the tragic domino chain of improbable events just makes a person feel sad for the victims rather than scared for the “heroes.”
A messy clash of tone and style that never figures out the formula for its comedy concoction, “I Don’t Understand You” plays around on the fringes of a good idea, yet never finds its way to the center of one. Kroll and Rannells do their best to sell the story’s comedy and emotional bedrock. Still, they can’t stabilize the lopsided conceit of the setup or salvage the played-out humor made explicit in the title. [D]