Very few TV shows manage to make a real impact on the world, but there's no denying that America's Most Wanted did.
For more than 25 seasons, host John Walsh shared stories about our country's most dangerous fugitives, urging viewers with helpful information to call a special hotline.
Tips from the show's viewers helped catch more than 1,000 criminals, including over a dozen from the FBI's Most Wanted list.
But very few of the show's fans realized that Walsh was trying to solve a murder case in his own family, a cold case that baffled police for decades.
The story begins in 1981, at a department store in Hollywood, Florida, where Walsh's wife, Revé, and their six-year-old son, Adam, were shopping.
Revé took her eyes off Adam for just a few moments to look in a different aisle, and when she returned the boy was gone.
Police were called, teams of men with dogs searched the area, and even a helicopter looked for signs of Adam, but he had vanished without a trace.
It was two weeks before Adam's remains - only a severed head - were found in a nearby canal.
The case was heartbreaking, and it drew national attention. But even though there were no leads on Adam's killer, Walsh and his wife were determined to get justice for their little boy.
Just days after his funeral, they began campaigning to change the way police investigate missing children's cases.
Their efforts led to the passing of the Missing Children's Act and the founding of the National Center for Missing and Exploited Children, which introduced the famous missing children ads on the sides of milk cartons.
The couple became associated with unsolved crimes and the hunt for missing children, which is why Walsh was picked to host America's Most Wanted in 1988.
The show became just another part of Walsh's search for justice, but he admits that interviewing parents with their own missing and murdered children was hard for him.
"I'll always be the parent of a murdered child," Walsh explained in a Nightline interview in 2009.
"Adam will always be in my mind. Your heart is broken. It doesn't matter if it was six months ago or 27 years ago. Your heart is broken. People deal with it differently. Some descend into hell in different ways and you live in that hell."
But after decades of waiting and praying, Walsh and his wife finally received the justice they had been praying for.
One of the lead suspects in Adam's disappearance was convicted serial killer and pedophile Ottis Toole.
Toole and his partner in crime, serial killer Henry Lee Lucas, had falsely admitted to hundreds of crimes, so Hollywood police didn't take his claims very seriously in 1983.
As the years went on, it became obvious that Toole was the only likely suspect for the murder, and he confessed to the killing again just days before his death in 1996.
The Hollywood Police Department later announced that Toole was almost certainly the murderer, and apologized to Walsh for "investigative mistakes that transpired during the early years of this investigation," but the TV host wasn't interested in pointing fingers.
"Who could take a six-year-old and murder and decapitate him? Who?" he asked at a news conference about the case in 2008.
"We needed to know. We needed to know. And today we know. The not knowing has been a torture, but that journey's over."
Officially ending the murder case brought closure to Walsh and his wife in another, heartbreaking way.
Because Adam's head was evidence in a capital murder trial, police had been unable to release his remains to his parents for 27 years.
Today, Walsh is still helping victims find justice on his latest TV show, CNN's The Hunt.
He says that as long as there are grieving parents and family members like him, he'll keep fighting to raise awareness for their unsolved cases. And he hopes Adam would be proud of what he's accomplished.
"I think wherever he is, he is [proud,]" Walsh told Nightline. "I don't know, I hope so. I loved that little boy."
Did you know about his tragic family history?