Prosecutors say it was the suspect's "dream theft" - to simply snatch an expensive Stradivarius violin from an unsuspecting musician.
Never mind that Salah Salahadyn, 41, had already tried and failed at art theft.
He pleaded guilty in 2000 to trying to resell a 25,000 dollar (£15,230) statue to the art gallery owner from whom it had been stolen in 1995.
And his ex-girlfriend told investigators that while he had not stolen it himself he did plot the theft.
Salahadyn was sentenced to five years in prison for that crime.
Now he could face up to 15 years for separate theft, after he and another suspect were charged yesterday in connection with the January heist of a 300-year-old Stradivarius violin valued at 5 million dollars (£3 million).
A confidential source told police that Salahadyn talked about stealing high-end art, the criminal complaint said.
"Salahadyn explained that his dream theft was a Stradivarius violin because of its potential value and the fact that it could be snatched from the hands of a musician as they walk down the street," the complaint quoted the source as saying.
Salahadyn and a second man, Universal Knowledge Allah, 36, appeared in court yesterday charges of being a party to robbery. Allah is also charged with possessing marijuana.
Court Commissioner Katharine Kucharski ordered cash bail of 10,000 dollars (£6,100) for Salahadyn, citing a lengthy criminal record that includes theft and bail jumping, and 500 dollars (£304) for Allah, whose record is clean.
Allah's lawyer, Paul Ksicinski, noted that the criminal complaint says his client was not at the scene of the robbery. It does say Allah bought the stun gun used in the attack.
Many Stradivarius violins, crafted by renowned Italian luthier Antonio Stradivari, are owned by private collectors who lend them to top violinists to be played in symphonies.
Experts say a Stradivarius violin degrades with disuse but remains in good condition when played regularly.
Experts estimate 600 to 650 Stradivarius instruments remain - about half of what the master produced - and they can be worth millions of dollars apiece.
It would not be hard to find one. Symphonies that feature a Stradivarius often play up the fact in brochures, advertisements and local media.
For example, Frank Almond, a concertmaster at the Milwaukee Symphony Orchestra, gave newspaper and magazine interviews about the Stradivarius, built in 1715, that was loaned to him by a private owner, and he's discussed the instrument in podcasts.
He had just completed a performance on January 27 and was putting the violin in his vehicle when a man shocked him with a stun gun, he told investigators. He fell to the ground, and by the time he recovered the thief's van had sped away.
Violin thefts are generally rare, perhaps because thieves know the easily identified instruments would be hard to sell.
But the robberies seem to be increasing, and musicians should be more cautious, said David Bonsey, a New York-based violin maker and appraiser.
"It's just one of these really unfortunate things where there's really a loss of innocence," Mr Bonsey said. "We've seen a lot of this in recent years."
Police found the stolen violin late on Wednesday night in a suitcase in the attic of a Milwaukee home of Salahadyn's acquaintances. Police said the homeowner did not know what was in the suitcase.
The music industry breathed a sigh of relief when police said the violin appeared to be in good condition.
But the theft also rekindled conversations about how to balance keeping the violins safe and making sure the public has a chance to enjoy them.
Kerry Keane, an international consultant for musical instruments from Christie's, said his clients who own Stradivarius violins are rethinking what to do with them.
Many bought the violins with the philanthropic intent of lending them to top virtuosos, he said, but as the violins increase in value, so does the risk.
"One client is considering buying a lesser grade of violin he can lend out," Mr Keane said.
"That's my greatest fear - that this will add hesitance to the philanthropists who buy them so they can be played in public."