By May 1893, Chicago's World's Fair is in full swing. Dr. H.H. Holmes welcomes visitors to his hotel, a block-long structure designed to lure eager, young women into his clutches. Before long, Holmes makes each mysteriously vanish, never to be seen again.

Dr. H.H. Holmes is America's first serial killer. He built his Castle with stolen money and keeps business brisk with stolen bodies. But when detectives begin closing in, Holmes invents new scams... in order to fund his fateful, final escape from Chicago.

Dr. H.H. Holmes, owner of Chicago's World's Fair Hotel, designed his entire Castle with murder in mind. But when forced to choose between wife and mistress, his next victim might not be his easiest.