Rosemead, in theaters nationwide Jan. 9, is inspired by the devastating true story of Lai Hang, a 49-year-old mother dying of cancer who fatally shot her schizophrenic son George, 17, while he was sleeping because she was afraid he was going to carry out a mass shooting.

The film, adapted from a 2017 Los Angeles Times story about Hang by Frank Shyong, stars Lucy Liu as Irene, who is trying to keep her son Joe’s (Lawrence Shou) schizophrenia diagnosis secret from the other parents in her Asian American community because of a taboo around mental health issues. She’s skeptical of his therapist, who wants Irene to play a larger role in sessions, and she’s worried about who will take care of him after she dies.

Here’s what to know about the true story that inspired the 2025 movie. 

The real family that inspired Rosemead

Lai Hang went to grade school in Laos and spent her teenage years in Hong Kong. She went to college to study graphic design in Tokyo, and in 1992, moved to the U.S., where she married her husband Peter and opened a printing shop in Alhambra, California. Because of the shop’s success, they were able to buy a house in a gated community in Rosemead. Their son George was born in 1998.

In 2012, Peter was diagnosed with cancer and died during George’s freshman year of high school. George’s personality started to change, and he withdrew from friends. The Los Angeles Times reports that some time after his father’s death, George was diagnosed with schizophrenia.

Hang didn’t feel like she had anyone to talk to about her son’s diagnosis because of the way she was raised. Many Asian Americans face a stigma reaching out for mental health services and “were raised to believe the proper way to respect another family's pain was to give them privacy and spare them the embarrassment of public suffering,” Shyong writes in the Los Angeles Times.

The mental health crisis in Rosemead

Lucy Liu in Rosemead. Vertical

In the film, Irene overhears Asian American moms gossiping that they’ve seen her son go to the community’s family services center and must be on medication—and thus must be possessed by an evil spirit. 

Joe is plagued with visions of his dead father during his therapy sessions and hears disembodied voices whispering while hanging out with friends. He is frequently paranoid, running away from home at one point in the film and fleeing his classroom during a school shooting drill and pacing in the hallways. School administrators alert Irene that he’s been sneaking into the school building after hours.

As the movie shows, Hang’s son really did get “fixated” on mass shooters, like Dylann Roof, the white supremacist who shot nine people at an Emanuel African Methodist Episcopal Church in 2015 in South Carolina. In real life, a few weeks after the shooting, Hang started the process of buying a handgun—the same day that she learned she had just months to live.

In the film, Irene initially goes to the gun store because she wants to know if the salesman recognizes her son. On his computer, she has found web browser tabs with coverage of school shootings, as well as firearm specifications. She also found a map of the school he had drawn, with skulls and words like “hell” written all over it, along with drawings of dead bodies and written phrases like “nobody likes you.” The firearms salesman says that he was looking at gas masks the whole time.

George’s final days

Records from the Los Angeles County Sheriff helped Shyong piece together Hang’s final days with her son. On July 27, 2015, she picked up her new handgun and checked into a motel with George. In the movie, the hotel they check into is one where, as he shares in therapy, he has happy memories of dancing on the beds with his mother and father as a young boy.

As Shyong reports: “When George fell asleep, Hang shot him twice in the chest, then crawled into bed beside him. For several hours, she stroked his hair as his blood soaked into the mattress. She wanted to say goodbye, she told the officers who responded to the scene.”

In the film, a night at the motel where Joe had fond memories is part of his 18th birthday celebration, in which Irene gets him sneakers he’s been eyeing. Then, she aims the gun at him and assures him that they will never be apart before shooting. Irene collapses to the ground screaming, drifts off, and when she wakes up, she calls 911. The film ends after Irene has died, with one of her friends lighting a match, about to burn photos of Irene and her son—per Irene’s last wishes—but she can’t bring herself to do it.

Hang told a detective with the LA County Sheriff’s office that she killed her son because he was obsessed with violent video games, and she was afraid he was going to become a mass shooter. She emphasized that she killed him to save the lives of others. “She didn't shoot herself, she told authorities, because she wanted to punish herself for what she had done,” Shyong reported. 

Hang did go to prison, where she lost vision in her left eye and suffered from paralysis because of her illness. As she was awaiting trial, a judge determined that her cancer qualified her for a compassionate release to a nearby hospital, where she died in December 2015.

Perhaps the saddest part of the story is that, while killing her son may seem like a last resort, Hang wasn’t really out of options. As Shyong writes in the Los Angeles Times: “George was about to turn 18, at which point he would be beyond Hang's legal control. But she could have asked a court to find him incapable of handling his own affairs and appoint a conservator. She could have convinced police or mental health professionals that he was an immediate threat to himself or others and had him taken into protective custody. That might have led to long-term psychiatric care.”