Recently “Beautiful Boy” recounted the long, unhappy history of a father trying to help his drug-addicted son. By contrast “Ben Is Back” covers a much shorter period of time—little more than a day—but Peter Hedges’ film also focuses on how a parent deals with a child who may be a hopeless addict.

In this case, however, the parent is the boy’s mother, Holly Burns (Julia Roberts). Just as she’s preparing Christmas for her family—her second husband Neal Beeby (Courtney B. Vance), her daughter by her first marriage Ivy (Kathryn Newton) and Lacey and Liam (Mia Fowler and Jakari Fraser), her kids with Neal—there shows up unexpectedly on her doorstep her son Ben (Lucas Hedges, writer-director Peter’s son).

Ben has been in drug rehab for seventy-seven days, and claims to have been given permission to go home for the holiday. His arrival turns the household upside-down. Neal and Ivy are deeply suspicious—Ben’s earlier visits home have ended disastrously—but Holly is determined to give him a chance to prove himself, though with severe restrictions. He can stay one day, provided that he take a drug test and is never out of her sight. He readily agrees.

But ghosts of times past have a habit of reappearing. The simple act of getting ornaments from the attic reminds the family that it’s where Ben used to hide his stash. A visit to the mall involves a meeting with one of Ben’s old comrades, as well as one with an Alzheimer’s-afflicted doctor (Jack Davidson) whom Holly blames for getting her son hooked on painkillers. The trip is so unnerving that Ben feels the need to immediately attend a narcotics anonymous meeting, where he speaks about his experiences—perhaps honestly, perhaps not—while bumping into a girl (Alexandra Park) whom he tries to help, or maybe uses for his own ends.

That’s one of the continuous points the picture makes—that however sincere about going straight he might claim to be, Ben cannot really be trusted. He admits what Neal and Ivy are quick to say—that he could very well be lying through his teeth. Even Holly knows that all too well.

Still, despite the bumps the family is getting by until they attend the Christmas pageant at church. There they encounter Beth (Rachel Bay Jones), the mother of Ben’s onetime girlfriend, who overdosed after he’d gotten her hooked. And when they get home they find the house broken into and ransacked, and the family dog gone. Ben immediately realizes that it’s the work of somebody holding a grudge from the time he was dealing, and he and Holly go into the night to track down the culprit and retrieve the animal.

What follows will involve a meeting with Spider (David Zaldivar), one of Ben’s still strung-out friends now on the street, and his old boss Clayton (Michael Esper), who feels that Ben still owes him—as well as a further meeting with Beth. Things grow darker and darker as mother and son get separated and it’s unclear whether Ben will be able to stay the course and survive the night. True to life, the picture doesn’t offer a pat, easy resolution.

It does, however, afford strong performances down the line. Roberts has never been better; in her hands Holly is a gaunt, emotionally shattered woman, desperate to save her son but distraught over the fact that he might be a lost cause already. Hedges matches her, managing to convey both Ben’s shiftiness and his vulnerability, while Vance and Newton convincingly capture the doubts Neal and Ivy have about the likelihood that he’s relapse. The supporting cast is fine across the board, with Jones especially effective as a mother who despite her loss can still feel Holly’s pain, and Zaldivar etching a shattering portrait of a lost soul. On the technical side, Hedges, production designer Ford Wheeler and cinematographer Stuart Dryburgh give the film an appropriately raw, often ugly look, and editor Ian Blume helps to bring nervous energy to the visuals, especially in the hectic final reel.

Though set at Christmas, “Ben Is Back” is hardly standard holiday fare; you leave it emotionally shaken rather than stirred to express the joy of the season. It’s a harrowing trip to the dark side of middle-class American society, offering a compelling depiction of the terrible cost drug addiction claims not only on its immediate victims but their families as well, with excellent performances.