Absolutely terrified. Robert Durst’s first wife, Kathleen Durst, feared for her life before she went missing in 1982.

Although the New York real estate heir, 75, was never charged with a crime related to his wife’s disappearance, the medical student — who has never been found — was afraid of him and wanted a divorce, according to her friend Ruth.

“One night, before she disappeared, she came over for drinks. My husband and I were having dinner with another couple. They came over, Kathie was drinking way too much I think because she couldn’t deal with everything that was going on and she stayed and stayed,” Ruth recalled in Us Weekly’s exclusive sneak peek of Robert Durst: An ID Murder Mystery part one. “Kathie started talking about something she had done and it was rather shocking. She told us that she took papers about the Durst Organization that she thought showed some illegal activity. She wanted to get a divorce and she was trying to use these papers I guess to coerce Bob into giving her money.”

Ruth added: “I was nervous because I knew he was violent. Our friend said to her, ‘Kathy, you’re going after an elephant with a pea shooter.’ She said, ‘Yes, I’m very, very scared and if anything happens to me, suspect fowl play.’”

The businessman, who is reportedly worth $100 million, will stand trial in California later this year for the 2000 murder of Susan Berman.

Watch the clip above to find out more about Kathie’s fears.

Robert Durst: An ID Murder Mystery part one will air on Investigation Discovery Monday, January 21, at 9 p.m. ET and part two will air on Tuesday, January 22, at 9 p.m. ET.

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