Kristine's Story

For three years, the disappearance of her sister has consumed Kathy Kupka's life.

By now, she has accepted the sad fact that her sister was probably murdered.

But what she will never accept, she says, is that someone is getting away with the murder. And, reports 48 Hours Correspondent Erin Moriarty, Kupka believes she knows exactly who it is.

The organizer of a group for relatives of missing people, Kupka says she knows her sister well. "She just doesn't not come home. She calls me all the time," Kupka says.

The man she blames for her sister's disappearance is Darshanand Persaud, known to everyone as Rudy. He was Kristine Kupka's chemistry instructor at college.

In 1998, Kristine was 28 years old and an honor student. She worked as a waitress and dreamed of becoming a civil rights lawyer.

Despite her busy schedule, she still found time to call her sister every day. And she called her mother, Elaine Bodell, at least once a week.

Bodell says she talked to her daughter about everything: "She was always forthright, honest, and she trusted."

According to the Kupka family, she and Persaud didn't date while he was her teacher. But when the semester ended, the relationship began.

"The guy is intelligent and good looking. That appealed to her," says Kristine's mother.

Her sister describes the relationship with Persaud as a "crush", saying it was "initially not a big deal."

But when she brought him home to meet her roommates, not everybody was as taken with Persaud.

Ozlem Ackadag was Kristine's close friend as well as her roommate. She says she had an immediate distrust of him: "He is good looking. But his eyes...his eyes are really cold."

If that was true, clearly, Kristine didn't see it. And in the summer of that year, Kristine told her friends and family what she thought was good news: she was pregnant with Persaud's baby.

But according to Ackadag, Persaud did not want any involvement with either Kristine or the child.

"He just went crazy and said 'No, it's going to ruin my family. I want nothing more to do with you,'" says Kristine's mother.

But there was something else that took Kristine entirely by surprise: Rudy Persaud was married.

Says Kathy Kupka, "She was so shocked when he told her he was married. It was shocking. We were all shocked."

Ackadag says Persaud tried to convince her to have an abortion, adding, "it didn't make any difference how much he ranted and raved, she was going to have this baby with or without him."

There was one thing she did want from Persaud. "She was very clear that she was going to put Rudy's name on the birth certificate and that he might be responsible at some point when she went to law school for helping with money,"says Kathy.

And that, Kristine told her friends, made Persaud absolutely furious.

"I spoke to her four days before she disappeared and she said 'if anything happens to me, it was Rudy who did it. Just go to the police, because Rudy did it to me,'" says Kristine's friend Suzie Riordan.

But Kristine's friends acknowledge that Persaud never specifically threatened her and that some part of Kristine was still in love with him.

Despite whatever fears she may have had, on Oct. 24, 1998, Kupka agreed to meet Rudy Persaud one more time. She told friends he wanted her help cleaning his new apartment. She said he could pick her up at her house.

Persaud arrived about noon and they left the house together. And then Kristine simply disappeared.

Twenty-four hours later, Kathy went to the police. She told them about Persaud and said he had the motive and opportunity to murder her sister.

But with no physical evidence linking Persaud to Kristine Kupka's disappearance - no body, no eyewitnesses - there was no proof a crime had even been committed. The police could do nothing.

"I said, 'well what am I supposed to do?' Thy said, 'I don't know. Go find the guy and ask him what happened,'" recalls Kathy.

As it turns out, that suggestion was far more difficult than it sounds.

Read about Kathy Kupka's search for answers.

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