Inside Luigi Mangione's Dark Descent — and What Became 'Almost an Obsession' Before He Allegedly Killed Brian Thompson

Americans awoke to shocking news from New York City on Dec. 4, 2024. In a brazen predawn crime captured on surveillance video, Brian Thompson, 50, CEO of the giant UnitedHealthcare insurance company, was shot execution-style outside the Hilton Midtown in Manhattan by a mysterious hooded figure who escaped, setting off a manhunt in the crowded streets of the nation’s largest city.

Intrigue mounted when police recovered bullet casings at the scene labeled “delay,” “deny” and “depose”—words used by critics to describe an insurance industry strategy designed to reject claims—and investigators released widely broadcast images of their suspect, a young man with striking features and a flirtatious smile.

When police eventually tracked down the suspect at a McDonald’s in Altoona, Pa., on Dec. 9, the public was presented with an accused killer unique in the annals of crime: 26-year-old Luigi Mangione — who was arrested carrying what police claim was a manifesto describing his M.O. and how he had selected a prominent health insurance executive as a target — is an Ivy League graduate who allegedly turned into an anti-corporate assassin.

Charged with 11 counts of stalking, murder and terrorism in New York, and facing additional federal murder and terrorism charges that, if proven, could carry the death penalty, Mangione has pleaded not guilty and is headed back to court in New York City on Feb. 21 for a pretrial hearing. He is currently being held at the Metropolitan Detention Center in Brooklyn.

Surprisingly, as he prepares his legal defense, he has the moral and financial support of a large number of private citizens who appear to believe his alleged crimes were justified by anger over insurance industry practices.

After accepting donations of $300,000 to his defense fund, Mangione released a statement on a newly launched website saying he was “overwhelmed by—and grateful for—everyone who has written me to share their stories and express their support.”

Now a new documentary, Who Is Luigi Mangione?, airing on ID and streaming on Max, traces the path of a once-promising student who allegedly transformed into a radical killer, as well as the ascent from humble origins of Thompson, the CEO of one of the nation’s richest corporations, who prosecutors say became an assassin’s target.

It’s the story of two men who, at one point in their lives, shared a lot in common before taking different directions and, authorities claim, ending up together at the scene of a horrific crime on a Manhattan sidewalk.

“They were both their high schools’ valedictorians, both who everyone expected would be incredibly successful,” says TV host and legal analyst Dan Abrams, who produced the documentary. “And based on the evidence that we’ve seen so far, it sure seems like their lives intersected.”

Born into a wealthy family in Maryland, Mangione attended Baltimore’s prestigious Gilman School, graduating in 2016 as the popular top student of his class. Says family friend Giovanna Blatterman in the doc: “He also had enough smarts to get into the University of Pennsylvania. It’s like you don’t have to brag when that happens—it speaks for itself.”

But while studying computer science, Mangione, who had Lyme disease, developed brain fog, a debilitating symptom that attacked his thinking and decision-making. In Reddit posts, he detailed his struggles, noting that he had to stop playing chess with his roommate because he couldn’t remember strategies. He was deeply frustrated.

“The brain fog becomes almost an obsession [for him] because it’s something that he can’t overcome,” says criminologist Casey Jordan.

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After graduating with both a bachelor’s and a master’s degree in 2020, Mangione eventually moved to Hawaii, where, while surfing, he suffered a life-changing back injury. He underwent surgery in 2023 and posted X-ray images of multiple screws in his lower spine from the operation. He claimed to have never fully healed.

Increasingly isolated, Mangione was still active on social media in early 2024, when he posted a positive review of “Unabomber” Ted Kaczynski’s manifesto on Goodreads. But after a trip to Japan focused on self–discovery, Mangione dropped off the map.

“I followed up in March, April, May—just a text message checking in,” says R.J. Martin, a friend from Hawaii. “And I didn’t hear from him.”

Mere weeks before the murder of Thompson, Mangione’s mother reported him missing to police in San Francisco, where she believed her son had been staying.

“The fact that even his mother didn’t know where he was would seem to indicate he really had made a big decision to prepare for this incident” in New York on Dec. 4, says Abrams.

When police arrested him days later, they found a 3D-printed “ghost gun,” fake IDs and a letter to “the feds” that reportedly stated that the “parasites” in the health insurance industry “had it coming.”

As for what’s next for the defendant, Abrams does not believe Mangione will mount an insanity defense.

“That would defeat the entire purpose of what he allegedly did and why he did it,” he says. “I would expect they’ll challenge the evidence as presented in court and hope there are jurors who sympathize with him.”

And if Mangione does argue his defense in court—as prosecutors detail the shocking circumstances of Thompson’s death—it will be one of the most widely followed trials in American history.

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