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Saturday 10/9c: Desperate Measures

Dennis Koula was a wealthy businessman who continued to work even though he'd earned enough to retire many times over. His wife, Merna, was a substitute teacher, and just like her husband, she loved to work. Then one day in May 2010, neither one showed up at work. They were found shot dead in their home.

The case shocked residents of La Crosse, Wis., where the Koulas were respected members of the community, seemingly loving parents to their grown children, Eric and Cindy, and enthusiastic grandparents.

"It was an assassination," says John Christophersen, a former special agent with the Wisconsin Department of Justice, who investigated the case "This is somebody that was lying in wait for them, prepared to execute them."

It was Eric who found his parents in their home and called 911. But who would want the Koulas dead?

The investigation would lead in many directions, including a tip from a neighbor – a banker – who tells police he had gotten death threats. And, as it turns out, a Google map search for his address actually points to the Koula house.

Was the person threatening the neighbor misled by the online maps, or were the Koulas killed by someone they knew? Correspondent Peter Van Sant investigates Saturday, Feb. 9 at 10/9c on CBS.

Watch a sneak peek

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