The subject of today’s episode is Henri Landru, the most notorious serial killer in French history. He placed advertisements in Paris newspapers in the late 1910s, preying on lonely women left behind as French soldiers marched off to war. While he would eventually be tried and convicted on twelve counts of murder, Richard Tomlinson, the author of “Landru’s Secret: The Deadly Seductions of France’s Lonely Hearts Serial Killer”, believes the actual murder count to be higher, and he explains why.