Polly (Kristen Wiig) wants Freddy (Sebastian Silva) to help her have a child in “Nasty Baby,” but it’s not as easy as she had hoped it would be. (The Orchard)

“Nasty Baby,” the latest film by Chilean writer-director Sebastián Silva, is provocative to the point of unpleasantness. Though the cast is full of recognizable character actors and the Bohemian urban setting is instantly familiar from a host of similar films, “Nasty Baby” is an awkward and grim affair. If it’s meant to be a joke, then Silva may be the only one laughing.

Initially, the filmmaker’s carefree style creates a unique sense of space. Silva himself plays Freddy, an artist who lives with his boyfriend Mo (Tunde Adebimpe) in Brooklyn. Freddy has agreed to provide artificial insemination for his friend Polly (Kristen Wiig), a single woman who wants a child. But when Freddy’s sperm count proves too low, he offers up Mo in his place. The inherent weirdness of the situation is not lost on Mo, who wants to be a good friend, but who also understands his limits.

As these two unlikely parents feel each other out, they must also contend with Bishop (Reg E. Cathey), their deranged, homophobic neighbor. The community accepts him as their local burden, until Bishop’s unhinged behavior turns into downright harassment.

On the plus side, Silva’s meandering screenplay has an authentic, improvised quality to it. Yet he invests too little in each concurrent plotline, instead having them clash with sudden, bloody violence. “Nasty Baby” starts as a wry comedy and eventually takes an abrupt turn toward horror.

Perhaps Silva views life and death as part of the larger, cosmic balance. Unfortunately, he squanders any chance to create depth by stripping his characters of sympathetic qualities, until raw terror is all they have. Ultimately, Silva’s uneven command of tone undoes whatever goodwill his actors have managed to generate. They — and we — deserve much better than this.

Zilberman is a freelance writer.

R. At the Angelika Pop-Up at Union Market. Contains coarse language, violence and adult situations. 100 minutes.