Directed by Leyla Yilmaz, this film finds troubled waters underneath the seemingly placid surface of a typical middle-class household in Turkey. As member of the school water polo team, Umut (Emir Özden) is under constant pressure to perform well in the pool and in his exams. All is not well for his parents, either. A compassionate doctor at a public hospital, his mother Selma (Senan Kara) spends her evenings secretly messaging a former flame on Facebook. Meanwhile, his father, Sinan (Yurdaer Okur), an engineer, endures daily intimidation from his new, much younger boss, whose demands lead him to drink heavily. The shaky stability of this nuclear family topples over when rumours about Umut’s sexual orientation spread through the school, causing the sensitive young boy to suddenly disappear without a trace.

Dealing with the loaded topics of growing pains, homophobia and bullying, the film expresses characters’ interior lives entirely through dialogue. The enveloping sense of uncertainty – Umut never acknowledges whether he is gay or not – isn’t helped by uninspiring visuals or sudden narrative revelations that announce mounting emotional turmoil. Certain plot points, such as an inheritance dispute, are introduced and never explored fully, and character motivation is at the mercy of the sequence of events: Umut’s bullies are threatening one moment then sob remorsefully the next. Social messaging appears to eclipse everything. What remains is a cautionary tale that functions better as a public service announcement than a humanist drama.

• Not Knowing is on digital platforms from 6 December.