Ashton Kutcher testified Wednesday in the trial of suspected serial killer Michael Gargiulo. He is facing two counts of murder in connection with the deaths of two women, one of whom Kutcher was friends with.

Ashley Ellerin, 22, was set to attend a post-Grammy party with Kutcher on February 21, 2001. But instead, prosecutors say Gargiulo snuck in and murdered her by stabbing her 47 times. Prosecutors have described him as a “serial, psychosexual thrill killer” who stalks and stabs his victims, all of whom are young women who live close to his Hollywood home.

“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.

Kutcher, 41, is one of 100+ witnesses who have or will testify in the trial of Gargiulo, 43. He reportedly confirmed his plans with Ellerin at 8:24 p.m. When Kutcher stopped by at 10:45 pm and she didn’t answer his knock or his phone call, he believed he’d been stood up.

“I knocked on the door. There was no answer. Knocked again. And once again, no answer,” Kutcher testified Wednesday. “At this point I pretty well assumed she had left for the night, and that I was late, and she was upset.”

He later told police that before he left he saw what he believed were red wine spills on the floor; prosecutors say the stains were blood.

“I didn’t really think anything of it,” he said.

When he learned of her murder, he spoke with police.

“I was freaking out,” he said during cross-examination, noting that his fingerprints were on the door.

“Don’t worry, you’re not a suspect,” Gargiulo’s attorney Daniel Nardoni told him.

“Thank you,” Kutcher replied.

“We believe now the evidence will show that was actually blood, and Ashley had already been murdered,” Akemon said.