OSPREY, Fla. – At the end of 1959, two families of four – one in Kansas, the other in Florida – were brutally murdered.

Two men were arrested, charged and executed in the Kansas case, and writer Truman Capote captured the horrific tale in his iconic true crime book, “In Cold Blood.”

The Florida murder of two parents and two children was investigated by dozens of detectives over the years, but it remained unsolved. Now, a detective is trying to prove that the men who were executed in Kansas were also responsible for the Florida slayings.