The trial of a former cryptocurrency whiz kid who at his height commanded a financial empire worth some $32 billion is underway in New York, with opening statements in Sam Bankman-Fried s criminal trial beginning Wednesday.

Prosecutors allege the 31-year-old stole $8 billion from FTX , the crypto exchange he founded, both for his personal use and to cover ballooning losses at Alameda Research, a crypto hedge fund run by his on-and-off girlfriend, Caroline Ellison.

Ellison figures to play a prominent role in the trial. The 28-year-old pleaded guilty to fraud charges in December and is expected to be a star witness for the prosecution.

In opening statements Wednesday, U.S. Attorney Thane Rehn cast Bankman-Fried as ultimately in control at Alameda, despite Ellisons title of CEO.

He was using her as a front in reality, he was still calling the shots at Alameda, said Rehn , noting Bankman-Fried founded the hedge fund before FTX. Alameda had secret access to FTX assets. Once Alameda had it, the defendant could spend it as he pleased.

The defendant took billions of dollars in FTX customer deposits from Alameda bank accounts and he spent it and the customers had no way to know that their money was being used in this way, said Rehn.

Bankman-Fried has pleaded not guilty to the seven-count indictment, which levels charges of conspiracy, fraud and money laundering.

Defense attorney Mark Cohen countered that Bankman-Fried didnt knowingly defraud anyone and believed the loans between FTX and Alameda were permitted.

Theyd have you think he was quite the villain almost the cartoon of a villain, he told jurors, describing Bankman-Fried instead as a math nerd who didnt drink or party.