SAN JOSE, Calif. (KRON) — Ex-Theranos CEO Elizabeth Holmes returned to the witness stand Monday morning in her own criminal fraud trial.

The 37-year-old former Silicon Valley star and her former partner, Ramesh “Sunny” Balwani, are charged with  two counts of conspiracy to commit wire fraud and nine counts of wire fraud related to an alleged a multi-million-dollar scheme to defraud investors with their blood-testing technology company.

Prosecutors spent three months showing the jury that Theranos technology was severely flawed. Patients testified about receiving bogus blood test results, including one woman who was told she suffered a miscarriage. She ultimately gave birth to a healthy baby.

The prosecution rested its case on Friday, and the defense wasted little time before calling its star witness to the stand: Holmes herself.

Holmes had a talent for charming powerful investors and politicians while she was a young CEO. She convinced sophisticated investors to believe in her vision, as well as pump millions of dollars into her startup company.

Former prosecutor Michele Hagan said Holmes has an ideal personality and skill set for winning over a jury.

“It’s her life after all, why not fight for it?” Hagan said.

The longer Holmes remains on the witness stand, the better her chances are for swaying the jury to her side, Hagan said.

For Holmes to be found not guilty, she only needs to plant seeds of doubt in just one of the 12 jurors’ minds.

Holmes shared memories with the jury about her beginnings as a Stanford University student who worked with a respected chemistry professor, Channing Robertson. Holmes dropped out of Stanford at age 19 with dreams of becoming the next Steve Jobs.

Holmes said she wanted to help save lives by giving patients access to rapid blood testing, using just a finger-prick of blood.

During direct examination on Monday, defense attorneys asked Holmes to explain how her startup company’s technology worked. She eagerly explained how her company evolved.

Holmes spoke in a higher voice than her usual low baritone voice.

Elizabeth Holmes
Elizabeth Holmes leaves the courthouse with her husband Billy Evans after the first day of her fraud trial on September 8, 2021. (Photo by Nick Otto /AFP via Getty Images)

Holmes’ defense tactic is centered on convincing the jury that she was a young businesswoman who tried her best to revolutionize healthcare, and failed.

Prosecutors argue Holmes wasn’t just a failure. She was a fraud who intentionally deceived investors and patients in a quest to become rich, adored, and famous. At one point, her company was valued at $9 billion and Holmes was America’s youngest self-made billionaire.

In 2015, Silicon Valley’s golden girl saw her dreams turn into a nightmare. 

Courtroom sketch of Elizabeth Holmes
Courtroom sketch of Elizabeth Holmes (Sketch by Vicki Behringer)

Her glittering public image was tarnished and her company fell apart after an investigative series by the Wall Street Journal exposed major problems with Theranos’ technology. State authorities shut down the blood lab.

John Carreyrou, the Wall Street Journal reporter who spearheaded Holmes’ downfall, was among dozens of reporters in the courtroom Monday listening closely to her testimony.

Holmes is facing up to 20 years in prison if convicted. Balwani will be put on trial separately next year.

This story will be updated. The Associated Press Contributed to this report.