In his scintillating directorial debut, Lin Jianjie invites us into the home of a middle-class Beijing family, where an alteration to routine disturbs the equilibrium, revealing a microcosm of sociopolitical intricacies in a post-one-child China. The only son of well-to-do urbanites, Wei befriends Shuo, a mysterious classmate. As the young man’s enigmatic persona leaves a strong impression on Wei and his parents, a bond forms between Shuo and the family. In particular, Wei’s cell biologist father is taken by the boy’s apparently studious nature, so different from his slacker son. As the relationship between Shuo and the family deepens, he begins to integrate into their household dynamic in the most precarious of ways. With shades of Joseph Losey’s The Servant and Bong Joon-ho’s Parasite, the film embarks on a microscopic examination of the infiltration of a familial cell within a larger national membrane.