Karen was 24 when they married, and had a job as an office assistant at a factory; Dyke worked in landscaping. There was no hint that just months after their wedding their lives would come to a violent end.
As correspondent Susan Spencer reports, in the early morning hours of July 6, 1986, a fire engulfed their home.
"My dad came over at 6 o'clock in the morning. I never will forget that. And he told me they had been killed," remembers Dyke's brother Tony. "He told me about their house burning. So we just naturally assumed they died in the fire, and it wasn't until two o'clock that afternoon that we found out they had been stabbed or murdered."
Justice moved quickly. Within a year, two men were arrested and convicted of the crime: 41-year-old Herb Whitlock, a part-time construction worker and small-time drug dealer, and his pal, Randy Steidl, 35, who also worked in construction and had several convictions for assault.
Prosecutors said the motive for the killing was a drug deal gone bad.
Both men said they were innocent, but no one was listening. That is until 1999, when journalism professor David Protess of Northwestern University gave his students the Rhoads murder as a class project. He told them to re-investigate the crime. To him, at least, the case didn't add up.
Protess has led classes on such projects before, investigating old crimes, and in ten cases they have produced evidence which helped free innocent men.
The job of finding the truth about the Rhoads case fell to students Kirsten Searer, Diane Haag, Greg Jonsson and Krista Larson.
Their professor admitted to having qualms about sending his students on this mission. "If that's the case and the two wrong guys are behind bars that means the actual killer or killers are roaming free," Protess told his students. "Number one, you're not going to stay anywhere in the immediate vicinity of the town. Number two, you're not going to tell any of the sources you talked to where you're staying. Number three, I don't want you to stay in the same place more than two nights in a row."
For the next nine months, the students would spend most weekends on the road, making the 180-mile trip from Chicago to the small town of Paris.
They would plow through police reports and court records to track down new leads and old witnesses wherever they could find them. The students interviewed dozens of people for their project.
Over and over again, the students recreated the crime scene in their minds, going back to that Fourth of July holiday weekend. "Dyke and Karen were sleeping in bed. The people came in. They attacked Dyke first, stabbing him in the back. Karen had time to wake up and maybe grab her glasses off her night stand, and then she was stabbed herself, mostly in the chest," explains Greg Jonsson.
Blood everywhere, but on the suspects.
"This young couple was tragically stabbed over 50 times. These men would've been covered in blood. There would've been blood in their automobiles, there would have been blood on their clothes. There would have been hair, fiber, something that linked them to the crime scene. Nothing did," says Protess.
Remarkably, the professor's skepticism is shared even by Dyke Rhoads' own family. "We weren't 100 percent convinced that they were the ones who did it," says Tony.
Their doubt is based on both the lack of physical evidence and on the supposed motive. The prosecutors said it was a drug deal gone bad, a theory Tony will not accept. But Dyke had met Whitlock half a dozen times, according to the testimony of a friend who had bought cocaine from Whitlock.
Tony says his brother Dyke was an occasional pot smoker and that Karen never used any drugs. "There's a big difference between somebody who's an occasional pot smoker and somebody who gets involved in with a drug deal that's gone bad, that's going cost you your life," says Tony.
The students also doubt the drug deal theory, but finding holes in this case wasn't as easy as it first seemed, because the juries heard from two people who said they had actually been there.