“We Don’t Live Here Anymore,” plays like a piece of music. It is understated, except when rage erupts, and the scenes of the complicated involvements shift between each other without fanfare. But crossed relationships are a tinder box in the suburban atmosphere. Mark Ruffalo plays Jack, a professor, who launches into a steamy secret affair with Edith (Naomi Watts), the wife of Jack’s best friend, colleague and running companion, Hank (Peter Krause). Hank is a struggling author who also teaches writing courses. He is terribly frustrated in his work. Hank in turn is attracted to Jack’s wife, Terry (Laura Dern), starved for affection in her marital relationship. Her unhappiness is reflected in her slovenly housekeeping and her resentment toward her husband, whom she still loves despite everything. But she is rebelling and her passions are unleashed when Hank makes his move. The children in the families are budding casualties of the arguments and disruptions.

Each actor is terrific, especially Watts in the way she pursues her affair and projects sexuality along with her overall attitude. Ruffalo expertly conveys Jack’s misplaced aggression against his wife’s behavior and his own selfishness. Krause captures Hank’s smugness, repressed feelings and stymied yearnings for success as a writer. Dern as Terry gives a magnificent performance and makes the most of fiercely emotional scenes of rebellion and impassioned expressions of her love for and devotion to her husband.