America's most prolific serial killer and most people have never heard of him.

Samuel little confessed to 93 murders across 19 states, and the FBI confirmed him as the most prolific serial killer in U.S history. The scariest part? Most of his victims' deaths were ruled overdoses or accidents. The system didn't even notice.

He sketched portraits of his victims from memory some still haven't been identified.

Do your research. The cold case era is NOT over!