Ashton Kutcher's past is going to be in his future.

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The Two and a Half Men actor dated a girl who was brutally murdered when he was just getting his footing in the acting world.

Daily Mail Online reported Thursday by way of Radar Online that Kutcher is prepared to testify against Michael Thomas Gargiulo in the coming months for allegedly killing Ashley Ellerin.

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LA Weekly reported in November 2010 that Los Angeles Police Department Detective Tom Small revealed Ellerin "had tons of boyfriends" at the time of her death on Feb. 21, 2001.

Kutcher was 23 at the time and Ellerin was 22 in 2001 when she was killed.

The day after Ellerin was slayed Kutcher was interviewed by detectives, in which he told them he called her twice that night to try to smooth things over since he had declined to see her earlier in the day.

He even drove to her place at 10:45 that night to see her lights were on and her car was parked outside.

He knocked several times and when she didn't answer he looked through a front window and noticed red stains, which he assumed were from red wine leading toward the bedroom.

He then left assuming she was just ignoring him, but her mangled body was just out of his view and the stains were actually her blood.

Ellerin's roommate Justin Peterson found her body and Kutcher's testimony is going to be crucial for prosecutors to prove the time of death and strengthen their case against Gargiulo. Gargiulo knew Ellerin and friends of hers said he had taken an intense interest in her in the time before her murder.