The novel “The Killing Machine” by Jack Vance was published for the first in 1964. It’s the second book in the Demon Princes series and follows “The Star King”.

Kirth Gersen agrees to work as a spy for the police but only after completing his mission does he discover that one of the criminals he had to face was actually Kokor Hekkus. Nicknamed The Killing Machine, he’s one of the demon princes Gersen wants to kill and was operating under a false name.

A trace leads Kirth Gersen to investigate a series of kidnappings carried out by Kokor Hekkus to obtain large ransoms. Interchange is an unofficial organization that acts as an intermediary between kidnappers and anyone who wants to pay the ransom. Gersen discovers that among Interchange’s “guests” is Alusz Iphigenia Eperje-Tokay, a girl who claims to come from the mythical planet Thamber, where Hekkus is said to have a base.