TAMPA — The person in handcuffs on the news seemed unrecognizable to many of Howell Emanuel Donaldson III’s closest friends.He wore a white jumpsuit and was surrounded by stout police officers who looked relieved after catching the man they were sure was Tampa’s most notorious killer.Even the name seemed strange to friends. They all knew him as "Trai." The label was even harder to comprehend: serial killer.Donaldson had randomly gunned down four people in Seminole Heights, investigators said, leaving the neighborhood terrified for 51 days.He was quiet, cocky, easy-going, his friends remembered. Average. He always had a basketball in his hands. He went from Alonso High School to St. John’s University in New York City, where he practiced for a brief time with the Division I team.He was a friend with whom many had lost touch, but not for any particular reason — people just grow old, and apart.He graduated in January, according to the university, returned to Tampa and bounced between jobs. He was fired from a customer support gig for absenteeism. He started working at the McDonald’s in Ybor City, where, police said, he left the gun used in the killings with a colleague who notified an officer Tuesday.The police chief said Donaldson, 24, was calm and pleasant when he talked to detectives. He admitted being the only one to ever possess the gun, but he didn’t confess to the killings.He didn’t say why he would shoot people or how he was connected to the Seminole Heights neighborhood.His close childhood friend learned of the news late, then stayed up all night in disbelief."My mom always commended him for his manners and likability, and she still says he was the most likable kid that you could possibly ask for," said Tyler Gimbert. "(She) started to tear up on the phone when I told her. My dad too. It just doesn’t make sense."• • •The boys from the middle-class neighborhood called themselves the Bay Crest Bunch. It was Gimbert, Donaldson and a handful of others — always sleeping over and playing pick-up sports. They rode the bus together to Farnell Middle School. Gimbert, now 25, remembers his parents were sticklers for manners; impolite friends were banned from staying over. But never Donaldson.One time, the boys came upon a nest of small garden snakes, Gimbert recalled. Donaldson wasn’t afraid. He grabbed a fistful of them and jokingly tossed them at his friends, prompting them to do the same. "Trai was always the brave one," Gimbert said.Gimbert said he was never too close with Donaldson’s parents and remembers his friend was often watched by an older sister. Court records show that Donaldson’s mother and father had a domestic dispute in 1997 that almost led to a divorce. His family could not be reached for comment Wednesday.Gimbert once fought with Donaldson’s cousin, he remembered, and they rolled into a canal behind his house. Donaldson stopped them and forced them to make amends.But people change, Gimbert acknowledged."I can only tell you what I know about him, who he was back in the day,’’ he said. "I don’t know how he might have changed or what could have led him to this. I’m repulsed by it, I really am. I feel so bad for the family members of the victims and Trai’s family.’’• • •Donaldson bounced between high schools, eventually landing at Alonso for part of his junior and all of his senior year. He played on the basketball team and graduated in 2011.A few years before, court records show, his parents entered into bankruptcy proceedings, reporting that they made $4,500 a month in 2008.Donaldson moved to New York for college, and at St. John’s, people quickly came to know him as a gym rat at the basketball court. He got a brief opportunity his freshman year to practice with the school’s basketball team, and another walk-on to the program remembered him as a guard who could dribble but was occasionally tripped up by pigeon toes.Donaldson liked to talk trash."He just had a mouth on him really," said Gerard Rivers, a fellow guard. "(As a walk-on), really your role is to just be humble and help where you can, and that wasn’t him.""He was a tough kid," said Sam Sealy. "He played with a chip on his shoulder."In his dorm, Rivers said, Donaldson was friendly, always sitting with his computer in the common lounge."He was so productive," Rivers said. "I knew he wanted to be there for school. It was a good school."• • •Still, it took Donaldson nearly six years to finish college. St. John’s declined Wednesday to release information about his academic history. In 2014, he was arrested in New York City, but police released no details Wednesday, saying the file was sealed.After school, Donaldson moved back to Tampa, a transition that was tough, said Ryan Keyworth, a friend from elementary school."We texted about life and going through hard times and how to pick ourselves up when going through adversity and overcome demons," Keyworth said.Donaldson worked in customer support at Ultimate Medical Academy from Feb. 13 to May 2 before being fired for not showing up to the office. He passed a background check to get the job. He appears to have no criminal record in Florida.Around Easter, Keyworth said, he and a group of buddies got together for a friendly game of pickup. When Donaldson was fouled, they saw rage in his eyes."His demeanor was different," Keyworth said. "It was something that was talked about among our close group of friends."They wondered what the problem could be, if the stress of not succeeding as a college basketball player had gotten to him. Or perhaps he had fallen in with the wrong crowd. Maybe he was having issues with a woman he was dating at the University of Central Florida."There was something going on," Keyworth said. "I didn’t want to pry because I figured if he wanted to talk, he would talk. But his diction changed. He was more aggressive in the way he talked. He had more of an edge. He had a fuse. I didn’t remember this kid being like this."The last time Keyworth heard from Donaldson was via text on October 3. That was the day the Tampa Police Department said he bought the gun used in the Seminole Heights killings.• • •Donaldson started working at the McDonald’s a couple of months before his arrest.Co-worker Gail Rogers said he never quite fit in. "He wasn’t a friendly person. We were all like a family," she said. "He wasn’t like the rest of us."They all talked about the killings, Rogers said, and they sometimes prodded Donaldson about his resemblance to a man police labeled a suspect in surveillance footage from the neighborhood."We would tease him and say he was the killer, because he looked like the pictures," Rogers said. "I called him the killer to his face. He didn’t like that."No one knew why Donaldson left the gun with a manager at the McDonald’s on Tuesday. Criminology experts said it was a bizarre turn."To give your gun to someone else sounds like he’s asking to be caught," said Northeastern University criminologist Jack Levin. "It just seems strange that the same person who would randomly kill complete strangers for the thrill of it would all of a sudden become remorseful."Bryanna Fox, a criminology professor at the University of South Florida, said it’s possible Donaldson was feeling the pressure from the police dragnet and was just looking for relief. Or he simply made a mistake.A recent traumatic episode in his life might have driven him to kill, she said, or he may have simply reached a tipping point from a series of smaller setbacks.For the people who know Donaldson, no explanation will ever suffice.Gimbert, his childhood friend, walked around their old neighborhood Wednesday.He went to a spot on the sidewalk where they had once all scrawled their names and pressed handprints into the wet cement.Everyone’s name was there, clear even a decade later. Except one.He couldn’t find Donaldson.Times senior news researcher Caryn Baird and staff writers Dan Sullivan, Charlie Frago and Jonathan Capriel contributed to this report. Contact Zachary T. Sampson at [email protected] or (727) 893-8804.