Phryne’s nemesis, and the suspected murderer of her little sister, Janey. Foyle is a former university lecturer and antiques shop owner. His deepest desire is to transcend this universe and transport himself to an imagined ‘otherworld’. Though he was never tried for the abduction of Phryne’s sister, he has been in jail for the past 14 years on a kidnap charge – and Phryne intends to keep him there.
Foyle wrote a letter to get Phryne's attention, promising to tell her what happened to her sister Janey in exchange for his release from prison. Phryne visited him in jail but resisted his bargain suggestion.
While investigating a murder at the very same circus that Janey went missing from, Phryne finds out that Foyle was the mastermind behind a prison escape that included himself and another inmate. For a period of time he is thought deceased as a result of a mix up during the escape, however it is later proven otherwise.
It is revealed that he was once a respected university lecturer at Melbourne University, however, after a trip to Egypt his sanity completely devolved and he became obsessed with the story of a King Memses and the pharaoh's "ascension" and intended to transcend into a higher plane of existence like the pharaoh. To do this believed he needed to murder four "goddesses" in correspondence with their certain birthdates. Phyrne's sister Jane was one of his victims, though his original target was Phryne herself as her birthday corresponded with the summer solstice. Jane was in fact grabbed by accident. After attempting to finish the ritual by killing Phryne, luring her by kidnapping and threatening harm to her ward Jane, he is eventually defeated and returned to prison permanently.