Halfway through “Beautiful Boy,” there is a scene where Nic Sheff (Timothée Chalamet), a recovering methamphetamine addict, is sitting on an old couch next to his mother (Amy Ryan). Nic is in rehab, and this is not his first attempt to go sober.

At one point during their visit, his mother, Vicki, looks at him and says, “you’re such a darling. You know that, right?”

Nic lays his head on his mother’s chest as tears stream down both of their faces.

“Beautiful Boy” is directed by Felix Van Groeningen and based on two memoirs, “Tweak” (2007) and “Beautiful Boy” (2008). The film chronicles the harrowing account of the promising and literary Nic’s turbulent addiction and his father David’s journey to save his child.

The film focuses on David’s pain and his confusion with how much addiction has affected his family. When Nic was a kid, David — played by Steve Carell — took him surfing along California’s beaches. After Nic found meth, David would drive aimlessly through San Francisco’s back alleys to find his shivering, frail son huddled in the pouring rain beside a dumpster.

Carell attempts to play up David’s layered nuances, but he misses the mark. Carell performs a concerned father rather than being a concerned father. His inauthenticity reverberates when he tries hard drugs in an attempt to understand his son or when he yells at Nic in the latest of a string of rehab attempts, struggling to sympathize with him.

However, there are moments when Carell displays emotional wealth. One is when he picks Nic up from his latest bender on the east coast and his son is sleeping on the floor of his father’s hotel room. David crouches down next to Nic and covers him with a blanket. These moments of profound effect happen when Carell does not talk.

That said, Carell does his best with the script he is given. The film’s shortfalls are more attributable to the script, written by Van Groeningen and Luke Davies, not the actor’s range.

The film fails to address the extreme privilege of the father-son duo. David is a journalist who has written for prestigious publications like the New York Times and Rolling Stone. The Sheff family lives outside of San Francisco. Nic’s stepmother, Karen (Maura Tierney), works as an artist. They live in a large, hill-top home that screams wealth. David hands his credit card to the director of Nic’s first rehab, as he does for the multiple rehabs to follow. When Nic drops out of college, there is no reference to tuition payments. When Nic needs his father on the east coast, David’s flight and hotel are booked without distress. Nic never has any encounters with police. After the story’s end, Nic writes for TV and film and he is never punished by his haunting past.

All things considered, when the film’s direction falls flat or Carell’s performance is unconvincing and lackluster, Chalamet consistently soared.

Throughout the movie, Chalamet is accessible and poetic. He plays the sharp edges of Nic as an addict with sensitivity and vulnerability. Chalamet weaves through the menacing nature of addiction with incredible warmth.

The audience believes in Nic, and Chalamet makes him believable.

One of this movie’s assets is Van Groeningen’s realistic portrayal of the recovery process. Fall down, then get back up and fall down again. Repeat. When you think Nic has finally gotten sober, he relapses.

When the film shows Nic, 14 months sober, speaking at Alcoholics Anonymous meetings and biking the California hills with his sponsor, the hope of a brighter and more stable future feels plausible for the sensitive and endearing protagonist. Committed to the reality of addiction, Van Groeningen shows that the highest of highs causes relapse for any addict just like the lowest of lows.

Early in the movie, when David answers a call from Nic’s first rehab clinic, a worker informs him that Nic had left the facility.

David, distraught and worried, questions whether they could get him back.

The clinic worker says: “Relapse is a part of recovery.”

When Nic goes into a coffee shop’s bathroom stall, pulls up his sleeve to find a vein covered by bruises all down his arm, he injects meth via needle. Whether he collapses or willingly lays down his head, the viewer feels a combination of both. Nic’s body is on full display in the bottom window of the bathroom stall. Light from the near window shines on Nic the way the sunlight streams through stained glass windows and spotlights its parishioners in a Roman Catholic church. For a moment, he looks like a renaissance painting, “Sleeping Cupid” by Caravaggio (1608). He looks like a sacrilegious relic.

The subject of “Sleeping Cupid” lays across a black background and has been historically interpreted to signify the abandonment of worldly pleasures. For a moment, the audience thinks this is the moment Nic dies of an overdose, but he doesn’t.

The real Nic Sheff has been sober for eight years, since the events of the film. He told media outlets that after he wrote his first memoir about addiction and read his father’s memoir about his painful experience and love for his boy, he still relapsed.

As I sat in the movie theater during this scene, I heard an older woman audibly weeping. I wondered if someone she knew was one of the 72,000 Americans who died from a drug overdose in 2017 or one of the 20.1 million Americans over the age of 12 who struggle with addiction.

“Beautiful Boy” reaffirms that addiction doesn’t care about how much money you have, who your parents are or where you grow up.

Elizabeth Donoghue can be reached at [email protected] or followed on Twitter @MsLizDonoghue.