VENICE (CBSLA.com/AP) — Philip Johnson was dying of pancreatic cancer when he brought his former wife, Thanh Tran, to the basement of his home in Venice, California. Under a tarp that was weighted down with bricks was a violin case with a combination lock.

He gave the case to Tran. He didn’t say a word about it, and she assumed it contained an antique violin that she had once bought for him.

It wasn’t until nearly four years later that Tran learned the truth: The case contained a famous Stradivarius that had been stolen from renowned violinist Roman Totenberg in 1980, likely by Johnson, who died in November 2011 at age 58.

Totenberg died the following May, at age 102. The last time he saw the Stradivarius was in 1980 when he left it in his office after a performance at a music school in Cambridge, Massachusetts.

In an interview with The Associated Press on Tuesday, Tran said her biggest regret was that she didn’t discover the instrument sooner and return it while Totenberg was still alive.

“I wish he would have told me before he died. Then I could have given it back to the Totenbergs,” Tran said in her first extensive comments since the violin was stolen. “I’m upset about that.”

Federal authorities gave the violin back to Totenberg’s three daughters, including NPR legal-affairs correspondent Nina Totenberg, last week. Nina Totenberg said her father had always suspected Johnson of stealing the violin, but authorities didn’t have enough evidence to get a search warrant.

Tran initially hoped there was some explanation for why Johnson, who scraped together a meager living as a concert violinist for most of his life, had the Stradivarius.

“I’m still digesting it. It blows my mind. I’m completely shocked,” she said. “Maybe it was just sitting there and it was too tempting. That’s all I can think of.”

Johnson had once been forced to sell an 18th-Century German-made violin. In the late 1990s, Tran bought it back for him, paying about $4,500. She didn’t think he owned anything more valuable.

This spring, while she was doing some home renovations, Tran said she and her daughters got curious. She and her fiancé pried the case open with a screwdriver.

“The violin looked magical but sad, with all of its strings busted,” she said.

She decided to get it appraised. Only when she began that process did she see the Stradivarius label inside the violin. At that point, she thought it had to be a fake.

Tran and her fiancé ended up meeting appraiser Phillip Injeian at a New York hotel in June. He told her he had good news — the violin was the real thing — and bad news. He said they needed to call the FBI.

Tran said she nearly fainted and wondered if she would be arrested. She spoke to FBI agents without an attorney.

“They asked me if I would be willing to let them take it, and I said, ‘Yeah, of course. It’s not mine. It’s stolen,'” Tran said. “They gave me a receipt.”

The FBI later informed her that Johnson had been spotted near the scene of the theft and was the only suspect.

At the time, Tran was a student at the University of Maryland. Five years earlier, she emigrated from Vietnam to the United States with her parents. She met Johnson in the early 1990s after a performance in Los Angeles. They dated for several years before marrying. They had two daughters and divorced in 2008.

“He was a complicated person,” Tran said.

Even now, she said, only one thing stands out as suspicious: Johnson would never leave the violin alone for long.

“I was looking back at some of the pictures of us, and there were pictures of us going for a hike, and he was carrying the violin case with him,” Tran said. “Wherever he went, he would always take it with him.”

Tran said Johnson almost certainly played the Stradivarius at home, but she doesn’t know if he performed with it.

Cellist Michael Fitzpatrick, who was part of a trio with Johnson in the early 1990s, said he’s not sure about that either, but he, too, remembers a quirk: the way Johnson carried his violin.

“He had this odd way of tucking the fiddle under his armpit,” Fitzpatrick said. “I had never seen anybody do that.”

Fitzpatrick said his friend must have been consumed by guilt.

“He was an eccentric, and so it didn’t seem ultimately beyond the stretch of the imagination that he could have done it,” he said. “To me, it falls in the category of tragic.”

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