Unlike the movies it's rarely a moment of revelation when a serial killer is caught but rather a number of small clues that lead investigators to the perpetrator.
In the case of the serial killer Richard Marc Evonitz, the clues that connected him to a number of deaths were particularly small.
Three girls are known to have been killed by Evontiz during the 1990s but before his death he confessed to his sister to even more victims.
His first victim was 16-year-old Sofia Silva who was abducted while sitting on her front porch doing homework in Spotsylvania, Virginia.
Five weeks later, investigators found her body in a nearby stream.
Just eight months later, he struck again and two sisters, Kati and Kristin Lisk disappeared. The bodies of the 12- and 15-year-old were found less than a week later, floating in a river.
The only clues were a few pink and dark blue fibres and a couple of strands of hair.
Special Agent Doug Deedrick, an FBI trace evidence expert, lead the forensic investigations on the case. He told ABC : "I said, 'Pink fibres, I think they look like a bath rug of some type.' Everyone was looking for this pink bath rug for me.
"With Sofia, for instance, I had some dark blue acrylic fibres that I was looking for because I found the same types on Kati and Kristin. And when I turned Sofia's shirt inside out, I actually pulled off eight or nine blue fibres."
A massive hunt was launched, with details of the cases cross checked with hundred of other open files.
Eventually Evontiz made a mistake.
He was tracked down by police after Kara Robinson, who was 15 at the time of her abduction by Evonitz, managed to escape and alert authorities. The killer ended up shooting himself after being surrounded by police.
Kara told Fox News she was left a "little angry" at his taking his own life instead of facing justice, adding: "My feelings have gone back and forth over the years to feeling relief that he killed himself because I never had to go to trial"
But investigators were left asking just how far he went before he was caught.
While searching his house they made a number of discoveries, primarily a pink rug.
Deedrick realised this rug matched the fibres found on the body of one of the Lisk sisters.
Another clue was in the handcuffs that Kara Robinson was wearing when she escaped.
They had fur lining, dark blue fur in fact.
The same dark blue as the fibres found on all three previous victims.
Those two key bits of evidence along with some fingerprints found in Evonitz' car was enough to solve the cases of the previous murders.
Police could tell the grieving parents who killed their daughters.
Deedrick recalled: "Early on, when I was talking with Patti Lisk, the mother of Kristin and Kati, I told her that when I get the right person, I'll know.
"And she reminded me of that some time later. And when I got the right stuff, I knew."
