Rachel Buffett, 25, was arrested on Tuesday on suspicion of being an accessory to murder.
Buffett was engaged to Daniel Wozniak in 2010 when he was arrested for murdering Samuel Herr and Juri Kibuishi.
Prosecutors say Wozniak killed Herr so he could steal his money to pay for the wedding and honeymoon. Wozniak then allegedly killed Kibuishi to implicate Herr. Authorities say Wozniak killed Herr in the base theater of the Joint Forces Training Center in Los Alamitos, and dismembered him to get rid of the body parts. Police later recovered Herr's remains after an extensive search at the El Dorado Park Nature Center in Long Beach.
Wozniak, who has pleaded not guilty, was a community theater actor based out of Fullerton. He's scheduled to appear in court Dec. 14 for a pretrial hearing. Wozniak and Herr lived in the same Costa Mesa apartment complex.
Authorities have focused on Buffett in the on-going investigation for the past two years. Police made the arrest after comparing interviews with Buffett and from various witnesses. Her specific involvement in the case was not released.
Buffett is being held on $1 million bail.