A grandchild of a self-made millionaire, Maryland native Luigi Mangione appeared set up for success. Mangione graduated from the prestigious Gilman School in Baltimore as valedictorian in 2016, and went on to earn two degrees from the University of Pennsylvania. Until late last year, he was living in Hawaii, according to media reports, and working for a California-based company as a data engineer.

Then, he seemingly fell off grid. His friends told news outlets they had not heard from him since the summer.

On Monday, Mangione was arrested in connection with the killing of UnitedHealthcare CEO Brian Thompson. He’s accused of gunning down the insurance executive, who was in Midtown Manhattan for a conference, on Dec. 4. Thompson was pronounced dead at a nearby hospital.

Police found Mangione more than 200 miles away, at a McDonalds in Altoona, Pennsylvania.

Here’s what we know about Mangione’s whereabouts in the years before shooting, as well as the subsequent search and arrest.

2019

May

In the summer before his final year at University of Pennsylvania, Mangione was a head counselor for Stanford’s pre-collegiate studies program, according to Stanford Daily. He wrote in his LinkedIn profile that he “designed lesson plans and taught artificial intelligence to gifted high school students” while supervising participants with “all aspects of residential life.”

2020

May

Mangione graduated with a combined master’s and bachelor’s in computer science in four years.

November

He started a job as data engineer at TrueCar Inc., a company based in Santa Monica. He was promoted in October of 2021.

2022

January

Mangione moved in to Surfbreak, a “co-living and co-working penthouse for remote workers” in Hawaii, according to Honolulu Civil Beat. He lived there until June 2022.

October

After receiving another promotion, Mangione moved to an apartment on South Street in Honolulu, according to KHON.

2023

Summer

Mangione left Hawaii presumably for an operation on his back, according to The New York Times. He visited Maui, the Big Island and Oahu around November and December, according to The Times, then went back to Baltimore to see his family.

2024

January

Mangione left a review of a book containing the manifesto of Ted Kaczynski, the Unabomber, on Goodreads. He wrote “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 … But it’s simply impossible to ignore how prescient many of his predictions about modern society turned out.”

February

Mangione traveled to Japan sometime in February, according to post on X from a Japanese professional poker player, Obara Jun.

March

A friend texted him “Miss you brother. Hope you are mostly recovered. Let’s catch up soon,” according to The Times.

April 15

Mangione texted the friend back, saying they should catch up soon, according to The Times.

May 20

The same friend texted him and did not hear back, according to The Times.

Aug. 31

Mangione left his apartment in Hawaii, according to Honolulu Civil Beat.

September

A wedding Mangione was set to attend took place at Hayfields Country Club, owned by the Mangione family, according to tagged social media posts. One of his friends repeatedly tried to reach him on X over the summer.

“I don’t know if you are okay or just in a super isolated place and have no service,” the friend wrote in a separate post. “But I haven’t heard from you in months. Your made commitments to me for my wedding and if you can’t honor them I need to know so I can plan accordingly.”

Nov. 24

10:11 p.m. — The suspected shooter arrives in New York City on a Greyhound bus at the Port Authority terminal. The bus originated in Atlanta and made six or seven stops on the way to New York. Police could not immediately determine where he got on the bus.

He then takes a taxi to the area of the New York Hilton Midtown and is there for about a half hour.

About 11 p.m. — The man takes a taxi to the HI New York City Hostel at 891 Amsterdam Ave., where he stays until the morning of the shooting. He presents an ID that police believe to be fake. Two roommates in a shared room that had bunkbeds never saw his face, police said, because he kept his mask on.

When speaking with an employee in the hostel lobby, he briefly pulled down his face mask and smiled — a moment captured on surveillance images that have been widely circulated by police.

Nov. 25

A user tagged Mangione on X, saying “Thinking of you and prayers everyday in your name. Know you are missed and loved.”

Nov. 29

The man was checked out of the hostel, where guests are automatically checked out if they don’t show at the desk by a certain time. Police don’t believe he stayed anywhere else and checked back into the hostel the next day.

Dec. 4

About 5:30 a.m. — The suspected shooter leaves the hostel well before dawn.

5:41 a.m. — He appears on video at 54th Street and Sixth Avenue, walking back and forth in the area of the Hilton hotel where UnitedHealthcare’s parent company, UnitedHealth Group, is holding its annual investor conference.

Police deduce that he rode a bicycle to the Hilton because it took him such a short time to get there. “Could he have stolen the bike? These are things we’re still looking into,” NYPD Chief of Detectives Joseph Kenny said.

At some point, he went to a nearby Starbucks and purchased a bottle of water and at least one energy bar before returning to the hotel.

6:44 a.m. — He shoots Thompson as the executive arrives alone, on foot, having walked from a hotel across the street. He then flees.

6:48 a.m. — The man enters Central Park by bicycle at the 60th Street and Center Drive entrance. It’s in the park and away from security cameras that police believe he discards a gray backpack.

6:56 a.m. — He leaves the park at West 77th Street and Central Park West, still on the bicycle.

6:58 a.m. — He passes another camera on 85th Street and Columbus Avenue, still on the bicycle.

7 a.m. — He’s at 86th Street, no longer with the bicycle.

7:04 a.m. — He enters a taxi northbound at 86th Street and Amsterdam Avenue.

7:30 a.m. — He’s near the George Washington Bridge and the bus terminal there. It offers commuter service to New Jersey and Greyhound routes to Philadelphia, Boston and Washington, D.C.

After the attack, investigators find the words “delay,” “deny” and “depose” written in permanent marker on ammunition at the scene. The words mimic a phrase used by insurance industry critics.

Dec. 6

Kenny and Police Commissioner Jessica Tisch reveal that investigators believe the gunman left New York City on a bus. Investigators say he entered the George Washington Bridge Bus Station but have not found video of him leaving or getting on a bus.

“It could possibly be a disgruntled employee, or a disgruntled client,” Kenny says of a possible motive in a briefing.

Police find what they say is the man’s backpack. Its contents are not disclosed.

Dec. 7

Police continue to search Central Park; scuba divers are seen scouring a pond. The NYPD releases additional photos showing the suspected shooter next to and in the back seat of a taxi. In both images he is seen wearing a blue, medical-style face mask.

Despite recovering a fingerprint from the Starbucks purchase and sending items for DNA testing, police have yet to publicly identify the suspect.

Dec. 8

Scuba divers are again seen at a Central Park pond. Police decline to comment on the investigation.

Dec. 9

9:14 a.m. — Police in Altoona, Pennsylvania, are dispatched to a McDonald’s to respond to reports of a male matching the description of the suspect in the shooting.

Luigi Nicholas Mangione, 26, is taken into custody on unrelated charges, according to the Altoona Police Department.

Mangione had a gun believed to be the one used in last Wednesday’s shooting, as well as writings suggesting “ill-will toward corporate America,” Kenny said on Monday. He also had clothing and a mask similar to those worn by the shooter and a fraudulent New Jersey ID matching the one used to check into the Manhattan hostel, Kenny said.