Adrian Raine did not go into his screening of Joker last Friday with lofty expectations. The neurocriminologist is a pioneer in researching the minds of violent criminals, having been the first person to use brain imaging to study murderers. Truthfully, the revered British researcher—who devoted decades of his life to understanding what makes criminals tick—just wasn’t that much of a Batman fan. So when he stepped into a Darlington, England, screening of the controversial Todd Phillips film, it was mostly to spend quality time with his nephews while on break from his professorial duties at the University of Pennsylvania.

But what Raine saw onscreen stunned him. According to the neurocriminologist, the script—from Phillips and Scott Silver—authentically traces the way a man could be driven to deeply troubling acts of violence by a combination of genetics, childhood trauma, untreated mental illness, and societal provocation. And though Raine was not sure how to pronounce Joaquin Phoenix’s name, the neurocriminologist was staggered by the nuance and grim grace the Oscar-nominated actor brought to the role—summoning the odd behavior, appearance, and social tics exhibited by those who suffer from certain personality disorders. Predicted the neurocriminologist, “He’s sure to be in the Oscar race.”

“[The film] was a surprisingly accurate prediction of the kind of background and circumstances which, when combined together, make a murderer,” said Raine, who was already considering integrating Joker into a forthcoming course at the University of Pennsylvania. “For 42 years, I’ve studied the cause of crime and violence. And while watching this film, I thought, Wow, what a revelation this was. I need to buy this movie down the road, make excerpt clips of it to illustrate […] It is a great educational tool about the making of the murderer. That threw me,” confessed Raine, still surprised by how much he appreciated the film. “I talk about all of these factors in the class, and honestly, it’s really hard to get a true-life story that fits all of these pieces together, let alone a very dramatic and stylized movie that illustrates these factors quite strongly. That was really a revelation.”

[Spoilers ahead for those who have not yet seen Joker.]

Raine rattled off a list of the factors depicted in Joker that contributed to Arthur Fleck’s disturbing violent turn. “Physical abuse is on the list, as is neglect and malnutrition as a kid,” Raine explained, referring to what Arthur discovers upon stealing his mother’s mental health files. “Being brought up in poverty is a risk factor. He’s adopted, and kids who are adopted are two to three times more likely to become criminal…certainly twice the rate of violence is well established. If you’re wondering why that is, it’s because with adoptions, the baby is separated from the mum for time—and that is breakage of the mother-infant bonding process in a critical period that we know affects personality development down the road.”

Raine was quick to add that “the link between mental health problems and violence is, of course, controversial”—like Joker is proving to be itself. “We don’t want to stigmatize mentally ill people as being dangerous people. But we do know that mental illness is a significant predisposition to violence, which we have to recognize so that people can be treated.” Raine said that the film was also surprisingly accurate in its depiction of the way that Arthur was incrementally driven to “reactive aggression.” He clarified, “Mentally ill people don’t go around serial-killing people—plotting a homicide or a bank robbery or a burglary. No, they react on impulse emotionally. It’s impulsive and emotion-driven.” And in the film, Raine pointed out, all of Arthur’s violence seemed authentic to him because it was “reactive aggression.”