In September 2006, Nina Reiser, a 31-year-old doctor and mother of two, disappeared.
Nina and her husband, Hans Reiser, were in the midst of a nasty divorce, and even without a body, it didn't take long for police to arrest Reiser and charge him with his wife's murder. Recently Reiser sat down with "20/20" in an exclusive pretrial jailhouse interview.
Asked if he thinks that Nina is alive today, Reiser said, "I think I'm a person who doesn't know."
Reiser was a child prodigy who dropped out of junior high school and enrolled at the University of California Berkeley at age 15. After college, he made his mark in the business world, starting a technology company and developing a new computer file system some consider revolutionary.
So how did a self-described "computer nerd" capture the heart of a beautiful obstetrician born in Russia? Reiser went to Russia looking for cheap labor for his computer business, and a bride. A dating service arranged a meeting at a café in St. Petersburg, but Reiser didn't fall for his date -- he liked the woman who came along to translate.
"She has the most beautiful voice," Reiser said. "When I first heard it I thought, 'This is someone special.'"
Just over a year later, Reiser married his Russian bride, who was by then five months pregnant. A bizarre wedding video shows a nontraditional wedding -- Reiser's best friend Sean Sturgeon, dressed in drag, was the maid of honor.
"I think that what interested [Nina] in Hans was that he was different from everyone else," said her friend Ellen Doren.
"Nina is entirely unique," Reiser said. "Try to imagine a well-educated Marilyn Monroe, who's a doctor."
The birth of their son Rory, now 8, and daughter Niroline, now 6, were happy times for the couple. "Nina was one of the best parents I've seen in my life," Doren said.
Reiser, who lost custody of his children in the divorce proceedings before his wife's disappearance, said, "I miss them so much. It's been so long."
But fights about how those children were being raised were at the center of a marriage that began to crumble. Doren said she was witness to the emotional disputes.
"They just could not agree on how to raise the kids," she said. "And there were very many, many fights and conflicts."
Reiser, whose work kept him overseas in Russia for months at a time, wanted more children and did not want Nina returning to work as a doctor.
"I ran the business and I expected my wife to take care of the kids," he said.
Reiser said he was "a bit naïve" when it came to his wife.
"The objective evidence doesn't support what I believed at the time. She divorced me the day she became a citizen. I don't know whether it was the exact day but same month -- close enough," he said.
Reiser also said that Nina, who ran the finances for the family computer business, was embezzling money.
Ramone Reiser, Reiser's father, believes "there's no question" Nina purposely got pregnant before the marriage.
"I have yet to get him to admit how much Nina was cleaning out the money," said Ramone Reiser. "He needs to stop thinking that something happened to her, or whatever. She took off and left him."
"The fact that she was gone wasn't a great surprise to Hans," said his attorney, William Dubois. "What came down on him like a ton of bricks was the fact that the police suspected foul play, and he was the primary suspect."