Although Michael Dorris’ 1989 book about his adopted son’s battle with fetal alcohol syndrome has been turned into a TV- movie tearjerker, The Broken Cord is a tearjerker with real emotional power behind it. Jimmy Smits stars as Dorris — he’s called David Norwell in Cord — a writer and teacher who, while still single, adopted a son, here called Adam, played at different ages by three excellent young actors — Frederick Leader-Charge, Michael Spears, and Frank Burning.

The movie follows Norwell’s growing realization that Adam isn’t just learning-impaired, as was first diagnosed. Talking to various doctors, he learns that the heavy drinking Adam’s mother did while pregnant caused irreparable brain damage in the child. The Broken Cord has a lot of medical information to get across, as well as sketchily drawn depictions of Norwell’s romantic life, culminating in his marriage to a novelist-poet (Louise Erdrich in real life) portrayed by Kim Delaney.

Despite its overstuffed, occasion-ally melodramatic quality, Cord contains a beautifully low-key yet urgent performance by Smits; and director Ken Olin, former star of thirtysomething, does a terrific job of conveying the close, complex relationship between this father and son. Adam (Reynold Abel in real life) died last year, only 23 years old, hit by a car; flawed as it is, TV’s The Broken Cord is a heartfelt testament to his life. B+