A portrait of parental grief etched with sensitivity and welcome touches of humor, “Rabbit Hole” boasts strong performances from Nicole Kidman and Aaron Eckhart as a couple trying to deal with the death of their young son, as well as from the supporting cast. It represents not just a distinct change of pace for director John Cameron Mitchell (“Hedwig and the Angry Itch,” “Shortbus”) but a major advance for him, too.

Adapted by David Lindsay-Abaire from his play, the picture charts how Becca (Kidman) and Howie Corbett (Eckhart) gradually come to terms with the loss of their four-year old son Danny. On the surface Howie appears to have come further in achieving closure, but it becomes clear that’s somewhat deceptive. While Becca is the more volatile of the two—occasionally bursting into angry tirades against not only her husband but her mother Nat (Dianne Wiest), who occasionally has the temerity to compare her sadness over the loss of her grown son to Becca’s, and her younger sister Izzy (Tammy Blanchard), a feckless, irresponsible sort who gets pregnant by free-spirited musician Auggie (Giancarlo Esposito)—Howie continues to mourn more secretly, shown in his protective attitude toward the videos of his son that he keeps on his phone and watches obsessively.

The arc of the drama has each of them confront their grief in different ways. After Becca acidly dismisses the members of the group therapy sessions they’ve been attending, Howie continues to participate by himself, and gingerly takes up with sad-faced Gaby (Sandra Oh), whose husband has left her over her failure to get past their child’s death; it’s a relationship that’s marked by some too-easy drug humor, but thanks to the affecting performances by both Eckhart and Oh, it avoids both mawkishness and crassness. Meanwhile Becca accidentally spots Jason (Miles Teller), the teen who accidentally ran into Danny as the boy chased his dog into the street, and secretly starts a friendship with him through which they both begin haltingly to heal. (The title comes from a comic book the boy’s drawing, which focuses on parallel worlds and alternative realities.)

It’s inevitable that in a story such as this, there are moments when the narrative threatens to stumble into maudlin, melodramatic territory. But “Rabbit Hole” avoids the pitfalls, thanks to the quality of Lindsay-Abaire’s writing and the rather surprising tastefulness of Mitchell’s direction, which eschews the over-the-top hysterics of his earlier work in favor of an edgy naturalism. He also draws well modulated, expressive performances, not just from his leads, who catch every nuance of their characters’ emotional journeys, but from Wiest, who paints a striking portrait of a woman who tries to hide her own pain behind a façade of joviality, and young Teller, whose shy, reserved demeanor can’t conceal his inner turmoil. Blanchard is a bit less successful, her brassy quality occasionally too hard-edged, but Oh uses the air of quiet resignation that seems her default mode to good effect, and plays the more humorous moments with real warmth.

Technically “Rabbit Hole” isn’t flashy, but the homely character of Frank G. DeMarco’s cinematography and the convincing suburban backdrop fashioned by production designer Kalina Ivanov, art director Ola Maslik and set decorator Diana Salzburg suit the material, while Anton Sanko’s spare score refuses to push the dramatic buttons too hard.

“Rabbit Hole” taps into the same vein of upper-middle-class grief that “Ordinary People” did thirty years ago, but while one can dismiss it—as many did Redford’s film—as a high-toned soap opera, it’s one that’s carried off with remarkable finesse and refinement—a domestic drama that offers some unexpected moments of levity while delivering a solid emotional punch.