Ashton Kutcher is gearing up to testify this week at the trial of serial killer Michael Gargiulo, who is charged for murdering several women — one of whom was a close friend of Ashton’s, Ashley Ellerin.

According to reports, Ashley had planned to attend a post-Grammy party with Ashton on February 21, 2001. Instead, prosecutors say Michael snuck into her Hollywood home while she was getting ready and stabbed her 47 times.

“We believe she had just exited the shower and was getting ready to go out with Mr. Kutcher when she was attacked from behind,” Los Angeles County Deputy District Attorney Dan Akemon said in a Los Angeles courtroom during the trial’s opening statements.

Ashton is one of many witnesses scheduled to testify in the trial. Prosecutors describe Michael as a “serial, psychosexual thrill killer” who stalked and then stabbed unsuspecting victims — all young women who lived near him.

Reportedly, the killer was working as a bouncer at the Rainbow Bar & Grill when he first met Ellerin, initially asking her if she needed help fixing a flat tire.

Her friends told police he lived less than a block from her, and would be seen parked outside her bungalow at odd hours, surveilling her home.

It’s possible that Ashton was one of the last people to speak to Ashley. On the evening of Feb. 21, 2001, she spoke with the actor at 8:24 p.m. to confirm their plans. But when Ashton called her again at 10:15 p.m. there was no answer.

We’ll keep you updated on the details of the case.