Luigi Mangione, the online version of him, was an Ivy League tech enthusiast who flaunted his tanned, chiselled looks in beach photos and party pictures with blue-blazered frat buddies.

He was the valedictorian of a prestigious Baltimore prep school who earned bachelor’s and master’s degrees at the University of Pennsylvania and served as a head counsellor at a pre-college program at Stanford University in California.

With his credentials and connections, he could have ended up one day as an entrepreneur or the CEO of one of his family’s thriving businesses. Instead, investigators suspect, he took a different path.

Police believe that Mangione, 26, is the masked shooter who calmly took out a pistol equipped with a silencer on a midtown Manhattan sidewalk last week and assassinated UnitedHealthcare CEO Brian Thompson. Mangione was arrested in Altoona, Pennsylvania, on Monday after an employee at a McDonald’s recognised him and called police. Officers said they found him with fake identification, a weapon similar to the one seen in video of the killing and a manifesto decrying the health care industry.

Mangione was charged on Monday in Manhattan with murder, along with additional counts of forgery and illegal weapons possession. And in the hours after his apprehension, his baffling journey from star student to murder suspect began to come into focus.

Mangione was in regular contact with friends and family until about six months ago when he suddenly and inexplicably stopped communicating with them. He had been suffering from a painful back injury, friends said, and then went dark, prompting anxious inquiries from relatives to his friends: had anyone heard from him?

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In July, one man tagged a social media account that appeared to belong to Mangione and said that he hadn’t heard from him in months. “You made commitments to me for my wedding and if you can’t honour them I need to know so I can plan accordingly,” the man wrote in a now-deleted post.

Those six months will most likely become a focus for investigators as they try to piece together what connection Mangione may have to the killing — and what he was doing in the time that no one could find him.

Mangione left behind a long series of postings about self-improvement, healthy eating and technology — and a review of the Unabomber’s manifesto.

Bullet casings left at the scene, scrawled with words such as “deny” and “delay”, left authorities and the public wondering if the shooting was payback for health care insurers rejecting claims.

In the wake of the attack, social media seethed with resentment against the insurance industry, and the unidentified suspect became, to some, a folk hero.

Mangione came from a privileged upbringing, part of an influential real estate family in the Baltimore area.

His grandfather, Nick Mangione Senior, and grandmother, Mary C. Mangione, purchased the Turf Valley country club in Ellicott City, Maryland, in the 1970s and developed the golf course community.

In the 1980s, the family purchased Hayfields Country Club in Hunt Valley, Maryland. It also founded the nursing home company Lorien Health Services, and Mangione’s father, Louis Mangione, became an owner. The family also owned radio station WCBM, which airs politically conservative programs, and has other real estate holdings. A cousin, Nino Mangione, is an elected member of the Maryland House of Delegates.

The family’s wealth and work with charity made it well known in Baltimore. Luigi Mangione was “just the last person you would suspect”, said Thomas J. Maronick Junior, a lawyer and radio host who knows several members of the Mangione family.

“It is just such a well-respected family and such a prominent family within Baltimore County,” he said.

Luigi Mangione attended high school at the prestigious Gilman School in Baltimore, where he wrestled and played other sports and was the valedictorian of his graduating class in 2016. In a graduation speech, he described his class as “coming up with new ideas and challenging the world around it”.

He thanked parents in attendance for sending him and his classmates to the school, which he described as “far from a small financial investment”. Tuition is currently $US37,690 ($59,000) per year for high schoolers.

Aaron Cranston, who became friends with Mangione during their time at Gilman, said he recalled Mangione as being particularly smart — perhaps the smartest at the elite private school. Even before college, Mangione had already made a mobile app where users could fly a paper airplane through obstacles.

Mangione was social, friendly and never particularly political, Cranston recalled. He was ambitious and carried his long interest in computer science towards college.

“He was a big believer in the power of technology to change the world,” Cranston said.

Freddie Leatherbury, 26, an accountant who lives in Catonsville, Maryland, graduated from Gilman with Mangione in 2016. He recalled Mangione playing soccer for the high school team and running track or cross-country.

“Those are both such disciplined sports. It says a lot about who he was as a student,” Leatherbury said. “He was very smart, a pretty big math guy, really well-read and quite well liked, to be honest. I don’t have any bad memories of him. He had a very healthy social circle.”

Race Saunders, 27, now a software developer who lives in California, recalled being “study buddies” with Mangione in high school. He remembered Mangione as a hard worker.

“We were all definitely leaning toward computer science,” Saunders said.

In college, Mangione excelled in that field. The commencement program for the University of Pennsylvania’s class of 2020 lists Mangione as a member of the school’s chapter of Eta Kappa Nu, an academic honour society for students in electrical and computer engineering that was founded in 1904. The society is selective, inviting only the top quarter of the junior class and top third of the senior class in those majors for membership, according to its website.

Mangione’s interest in computer games started at a young age, when he began exploring the community online, according to a now-deleted interview published on the University of Pennsylvania’s campus events blog in 2018. From there, the interview said, he wanted to start creating games himself and taught himself to code in high school.

“That’s why I’m a computer science major now, that’s how I got into it,” Mangione said in the interview. “I just really wanted to make games.”

After college, Mangione worked for, or had internships with, several tech companies, according to his LinkedIn profile and a former employer.

Mangione’s profile said he had worked as a software engineer at TrueCar, an online marketplace based in Santa Monica, California. The company said in a statement that he had not been an employee since 2023.

In recent years, Mangione lived for six months in Honolulu in a “co-living” space called Surfbreak that caters to remote workers.

R.J. Martin, founder of Surfbreak, said that when he met Mangione in 2022, he was interviewing to be among the initial 20 or so occupants paying about $US2000 per month to share quarters.

Martin described Mangione as a smart, accomplished and upbeat engineer. “Our mission statement is that we’re a community of givers and that we leave things better than we found them,” Martin said. “We look for people who are looking to give back. And he fit the bill. He was an ideal member for us.”

But Mangione was suffering from painful back issues, he said. “His spine was kind of misaligned,” he said. “He said his lower vertebrae were almost like a half-inch off, and I think it pinched a nerve.”

The problem, he said, became especially apparent when Mangione took a group surfing lesson with other members of the community. “For some reason, the motion — the arching, the looking up — was just the wrong thing for his back,” Martin said. “He was in a lot of pain.”

Mangione did not make a habit of complaining, and did not seem to be on any type of painkilling medication, Martin said. He even went rock climbing at a local gym, although he was always careful to climb down slowly so as not to jar his spine.

Still, Martin said, he and others in the community came to understand that the pain was no small matter to a young man yearning for a normal lifestyle. “He knew that dating and being physically intimate with his back condition wasn’t possible,” Martin said. “I remember him telling me that, and my heart just breaks.”

Mangione was cited for trespassing while he was living in Hawaii, according to court records, which said he had failed to observe a sign at the Nu’uanu Pali Lookout on Oahu on November 12, 2023. He was carrying an ID with a Towson, Maryland, address and was fined $US100.

His internet trail hinted at pain both physical and mental.

In January, Mangione left a review of a book containing the rambling manifesto of Ted Kaczynski, the Unabomber, on Goodreads, a social media site for bookworms.

“It’s easy to quickly and thoughtless write this off as the manifesto of a lunatic, in order to avoid facing some of the uncomfortable problems it identifies,” Mangione wrote of the document. “But it’s simply impossible to ignore how prescient many of his predictions about modern society turned out.”

One of Mangione’s favourite quotes, listed on Goodreads, was “It is no measure of health to be well adjusted to a profoundly sick society,” from Jiddu Krishnamurti, a religious philosopher and teacher.

The Goodreads page also included self-help books about health and the human body, including Crooked: Outwitting the Back Pain Industry and Getting on the Road to Recovery.

A social media account that appeared to belong to Mangione contained an X-ray image of a spine reinforced with surgical implants. The X-ray showed a spinal fusion, a procedure that uses screws and rods to fuse two levels of the spine to address a misalignment that can cause serious pain, according to Hasit Mehta, a professor at New York Medical College.

Cranston, the school friend, said he was forwarded a message this year from Mangione’s family saying the family had not heard from him in several months after his surgery. Relatives were hoping friends might know of his whereabouts.

Few, if any, did until his arrest on Monday morning.

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Saunders, the high school friend, was shocked by the news, but was sceptical that his classmate had suffered a psychological break.

“I would be surprised if it was some kind of mental breakdown,” he said.

For now, investigators will be looking for any additional clues that might link Mangione to the shooting. One thing they were examining was the handwritten manifesto that Mangione had in his possession when he was arrested, according to a senior law enforcement official.

“These parasites had it coming,” it said at one point, as well as “I do apologise for any strife and trauma, but it had to be done.”

At Mangione’s arraignment in Pennsylvania on Monday, a judge asked him whether he was in contact with his family.

“Until recently,” he replied.

This article originally appeared in The New York Times.

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