The Trophy Wife and the Tennis Pro

Police found no sign of a break-in at the Hartmann home. Other than the spent .45-caliber shell casings and Werner Hartmann's body, shot through with more than a dozen bullets, there was no sign of an intruder. So the investigators focused on Werner's family.

Uncovering motive unravels the mystery surrounding most killings. A murder happens for a reason, and if investigators can figure out why a person was killed, they can usually figure out who did the killing.

In the Hartmann case, detectives didn't have to look far. The person with the biggest motive for killing Werner Hartmann was lying on the floor of their office, asleep.

"When this thing first broke it made a huge splash," recalls former Chicago Tribune reporter John Gorman. "It was a front-page story. It was in a north suburb that doesn't have any murders; there was a millionaire involved; it was a big house: it had all the elements."

Investigators found out fairly quickly about Debra and her boyfriend, John Korabik. The insurance policies were also no secret. Debra started filing her claims almost as soon as her husband was in the ground, but insurance policies aren't proof of murder.

Weeks passed; nothing happened. The investigation stalled. Korabik moved into the big house in Northbrook.

Werner's daughters were frustrated. They had no doubts about who had been behind the murder of their father.

"It was so clear me, and to family, and to friends of my father," Stephanie Hartmann said. "It was just so clear to everybody that she was behind this. What was taking so long?"

But "knowing" who did it and proving who did it were two different things, and in the case of Werner Hartmann's murder they were far apart.

"The Northbrook Police Department simply could not put a case together as to who pulled the trigger," said prosecutor John Farrell.