The demise of Ross Magill began some three years ago.

Mr. Magill had fallen for a Vancouver man in 2005. Their relationship blossomed quickly, and Mr. Magill - always prone to move on a whim - uprooted his life to be with his new partner out west.

Later that year, the couple split, and Mr. Magill returned to Toronto a changed man.

So began what friends called a "downward spiral" of a gifted interior designer. Mr. Magill became addicted to drugs, sex and alcohol, and could not keep a job or apartment.

He grew promiscuous, bringing many younger men home to his latest midtown apartment, friends said. Monday night, he let two others in - and soon afterward he was dead, the victim of a stabbing attack in a city where few recognized the man he'd become.

Born William Ross Magill in Hamilton in January, 1944, he displayed a flair for design early on. He never went to design school, instead learning on the job wherever he worked - in Florida, New York, Toronto, Vancouver and Bobcaygeon, Ont., where his mother lived.

"He was a very talented designer, really a top-flight designer," said Diane Watts, a home furnishings designer who'd worked with Mr. Magill.

John Manuel, another Toronto designer, first met Mr. Magill at age 17.

"He was very well-liked. He was chock full of personality and devastatingly handsome," Mr. Manuel said. But Mr. Magill had a "very checkered career," he added, moving on a whim and starting over each time. "He was successful in Florida, and he threw Florida away," Mr. Manuel said.

Eventually, Mr. Magill, who friends say was HIV-positive, returned to Toronto to get the benefit of the Canadian health-care system. His mother, with whom he was very close, died a few years ago. Soon after, he moved to Vancouver. On Dec. 17, 2005, he called Ms. Watts and asked if he could move back and stay with her.

"[The boyfriend] threw him out, basically, and Ross was never the same after that," Ms. Watts said. "It just totally messed him up."

He stayed with Ms. Watts for two months, weeping often. She didn't believe he was addicted to drugs at the time, but knew he'd battled alcoholism. He moved out in early 2006, and after brief stays at two other apartments (one on Alexander Street in Toronto, where Ms. Watts suspects he picked up a drug habit), he moved into the building on Delisle Avenue, near Yonge Street and St. Clair Avenue.

Over the past five months, he rarely returned phone calls from friends. His only family, a sister, lives on the East Coast. While falling out of contact with his design associates, it appears Mr. Magill, at age 64, descended into a life of drugs, sex and alcohol.

"It was just a downward spiral," Ms. Watts said. "He was really on a descent into hell."

Friends say he continued to attend Alcoholics Anonymous meetings, but that he wasn't looking for help.

"Everyone was upset about it for him, and tried in big ways to help him," Mr. Manuel said. "It was getting to a point where I couldn't cope with his problems."

Mr. Magill became insular, only saying a quick hello to neighbours and choosing not to place his name in his building's front-door tenant directory.

He often brought in young male guests - "junkies," one tenant said - who neighbours believed to be lovers of his. "He got really mixed up in the wrong crowd," Ms. Watts said.

But Mr. Magill, a proud man who spoke in such a way that neighbours believed he had a British accent, was shy about the relationships with young men. He would often send his partners up alone in an elevator so as not to arouse suspicion, neighbours said.

On Monday night, two men knocked on the door of his second-floor apartment. Mr. Magill let them in while a 23-year-old man living with him, identified by neighbours as his boyfriend of three months, was in the shower.

Soon afterward, Toronto police said, Mr. Magill had been stabbed "multiple" times and lay dead in his home.

"I believe he knew his attackers - at least one of them anyway. He opened the door," Detective Sergeant Dan Nielsen said.

His 23-year-old guest heard the commotion and called police at 10:42 p.m. He has been interviewed by police - saying he saw two men flee but was unable to give descriptions - and is not considered a suspect, police said.

Officers are reviewing security tapes from nearby buildings and found cocaine in Mr. Magill's apartment. They have made no arrests.

His frequent guests didn't please the superintendents of the 104-unit building. Much like his friends, his neighbours warned him about the dangerous life he was leading, with young men coming and going.

"How can I say it nicely? I mentioned it many times, his 'friends,' " said Agnes Forika, 47, with a knowing wink. "I promised him: 'One of them will kill you, Ross.' "

Mr. Magill is Toronto's 30th homicide of the year. An autopsy is scheduled for today.