NASHVILLE (AP) — A federal appeals court upheld the convictions of an extortionist who called himself Dr. Evil who claimed to have stolen the tax returns of then-presidential candidate Mitt Romney and threatened to release them if he wasn't paid.

It was an elaborate plot where Michael Mancil Brown sent letters falsely claiming that he had hacked into PriceWaterhouseCoopers accounting firm and would make the tax returns public if the company didn't send him $1 million in Bitcoin, a digital currency. Dr. Evil is the fictional character portrayed by comedian Mike Myers in the Austin Powers movies, and Brown chose some features of the film series as signatures of his 2012 crime, according to an opinion issued Monday from the U.S. 6th Circuit Court of Appeals.

"The extortionist claimed to have stolen Romney's returns from PricewaterhouseCoopers, and he posted a taunting, digitally altered image of Mike Myers' Dr. Evil, wearing a Secret Service badge in the lobby of the account firm's office in Franklin, Tennessee," the opinion said. In the letter to the firm, Brown threatened that other parties would be competing to pay for the information. Brown also sent letters to the Republican and Democratic parties of Franklin.

It turned out that Brown, who owned his own tech company at the time, never did have the tax returns.

The federal appeals court upheld the 38-year-old's 12 convictions for wire fraud and extortion. However, the court vacated his four-year prison term and ordered him re-sentenced because the punishment was wrongfully enhanced.

Brown's lawyer declined to comment.