Taking its European bow at Berlin after a premiere at Sundance, Lin Jianjie’s first feature focuses on a teenage boy, his parents and the classmate who becomes their surrogate second son.

Identified only by their last name, Tu, the husband and wife in Brief History of a Family have built their comfortably middle-class life together in accordance with China’s one-child policy. Now, in less restrictive times, a chance to expand their nuclear unit arrives in the form of their teenage son’s mysterious new friend. From shifting perspectives, writer-director Lin Jianjie examines the contained volatility of this four-person configuration. His stylistic choices can be spot-on or self-conscious in their artifice, but his debut feature reveals a talent to watch. With its intriguing performances, narrative restraint and unanswered questions, the movie delivers a strong pull of yearning as well as tantalizing currents of suspicion and dread.

The father (Zu Feng) is a biologist, the mother (Guo Keyu) a former flight attendant, information we learn upon Shuo’s first visit: Taking in the view and the spaciousness and the elegant consumer trappings (fine work by production designer Xu Yao), he asks Wei, “What do your parents do?” In an incisive and humorous signal of the class divide between them, Shuo requests soy sauce at the dinner table and Wei’s mother, somewhat taken aback, offers him four types of the condiment. Having chosen, he douses his rice with it, his gastronomical gaucheness provoking a shocked silence.

The helmer keeps the story centered on the stylish space of the Tu apartment, which, after a crucial offscreen incident, becomes Shuo’s home too. But well before that turn of events, Shuo has insinuated himself into the family. Moving through their apartment’s hallway, past the feng shui fish tank, he’s no mere wanderer but, in his quiet way, purposeful. He hears Mrs. Tu’s meditation tapes in one room, Mr. Tu’s Bach in another, and Wei’s video games in the boy’s bedroom. The first time he spends the night, he has no qualms about asserting his preferences when Wei lends him clothes.

In a late-night conversation with Wei’s mother, Shuo draws her out with an impressive off-the-cuff tenderness. Guo, who first made her mark onscreen as a teenager and for whom this film is a return to acting after a nearly 10-year break, offers a compelling portrait of gentleness, maternal warmth and regret. The heightened vision of her in the supermarket, not quite lost but incongruously fancied up, hints at some of the more surreal moments ahead from Lin and cinematographer Zhang Jiahao. Shooting in Chengdu, Hangzhou and Beijing, they create an unspecified city with an emphasis on its enormity, the edifices (and the produce displays) dwarfing the characters.

Zu brings a colder form of constraint, with revealing cracks in the surface, to the role of Wei’s father, who’s impressed by Shuo’s focus and drive. The boy’s ambition is precisely what Mr. Tu longs for from his son, who’s ordinary in his insolent teenage laziness and more interested in fencing than the advanced English program his father insists he enroll in. Soon, Shuo is taking Wei’s place in the parents’ Ivy League dreams, and literally stands in for their son on a family weekend getaway.

With minimal dialogue, the two young actors Sun and Lin evince a subtle reversal. Their unforced performances leave us to wonder, in Shuo’s watchful maneuvers and Wei’s increasingly stricken gaze, who’s helping whom, and who’s being honest — questions of identity mirrored in the reflective surfaces within the family home and their slightly confounding effect.

The boys, in their adolescent confusion and awakening, waver between the impulse to save and the impulse to hurt. There’s an undertow of potential violence to the drama, percolating in its dark, propulsive score by Toke Brorson Odin (Winter Brothers), its suspenseful sound design by Margot Testemale and Jacques Pedersen, and the unrushed precision of Per K. Kirkegaard’s editing.

There’s also a hallucinatory sensibility at times, and at others a scientific slant. Lin, who has a degree in bioinformatics, uses a circle motif that likens the four central characters to cells viewed on a microscope slide, and compares the coursing of blood through veins to people’s transit through city streets. Some of these visual gambits stop rather than deepen the story, but those pauses are momentary. If the biological metaphors don’t always click, the aching and perhaps dangerous dance among four wounded people never misses.