In the beautifully observed “Mutt,” which chronicles a day in the life of a transgender man who has recently transitioned, the dramatic tension doesn’t arise from the threat of violence or some horrible injustice. Instead, the most remarkable moments occur during relatively routine encounters, whether it’s running into an old flame, cashing a check, or picking up one’s father from the airport.

This is one of those sneakily good movies where at first nothing much seems to be going on, before the parts start adding up to a satisfying whole. “Mutt” turns out to be a well-crafted character study of not only a trans man, but also of the most important people in his orbit.

The story begins as Feña (Lio Mehiel, superb) is hanging out with friends at a New York nightclub. Feña, who was named Fernanda at birth, has assumed a gender-neutral Chilean name after undergoing top surgery. In the dance hall, a woman high on cocaine abruptly asks Feña whether he has a penis, and he handles the inappropriate question with aplomb.

But the night is just getting started.

Also at the nightclub is John (Cole Doman, excellent), who still carries baggage from his breakup with Feña and hasn’t seen him since the surgery. Both of them still have a strong physical attraction toward each other, and end up hooking up at a laundromat after getting soaked in the rain. The electric scene is a gripping muddle of complex feelings and desires, two people grappling with very different transitions in their lives.

These various transition struggles are at the heart of this riveting, well-acted movie, as Feña later gets a surprise visit from his truant half-sister Zoe (an appealing MiMi Ryder), who has issues of her own with her half-brother. The dynamic gets even trickier when Feña meets up with his father, Pablo (a soulful Alejandro Goic), who wants a closer relationship with his son but doesn’t know exactly how to do it.

Director Vuk Lungulov-Klotz is careful not to anoint Feña as a saint, painting him as just as flawed as the people around him. Though Feña is not confused about who he is, the young man is definitely confused about how people from his old life should fit into his new life.

Throughout the film, we feel the weight on Feña as seemingly easy daily tasks turn into nightmares, such as when he tries to cash a check that’s made out to Fernanda instead of Feña. Lungulov-Klotz handles both the awkward moments and weightier scenes with grace, honesty and sometimes humor. At the same time, he films the streets of New York with a gritty realism, which heightens the authenticity of the movie.

As the pieces of Feña’s past come into focus, we become more and more invested in his current journey. The final scenes are subtle yet powerful, a delicate reminder that no matter how difficult it is, we have to stay true to who we are.

David Lewis is a freelance writer.