Warlord of Mars: Dejah Thoris #21

Synopsis

Undercover in Zodanga, Dejah poses as a prostitute in order to spy on the operations of Mortus. Instead she is captured by Vas Argus and learns that the crime boss Mortus is really her old enemy Senneth Dor. He is using the brains of dead captives to create an army of machine men and has even turned her companion Gunbor into a mindless cyborg.