In 'Delphes', Zac meets Delphes, a young woman who has a premonition about the death of Paul. Zac agrees to investigate the case, and in the process, assists the Police in their investigation of a physician who is at the centre of an organ donor scandal. The story also introduces Vera Winston and Kevin the 'skunk', a judo instructor. It appears that the young woman's vision is true and in trying to solve the case, and protect Paul, Zac puts himself in the line of fire – justice will prevail but not without casualties. As an aside, Mrs Chan starts the hunt for the Holy Grail and finds something nearly as important.
'Delphes' is the 6th Zac Tremble Case File in the series Zac Tremble Investigates; the case files of the gay, Soho-based PI Zachary Tremble. 'Delphes' follows, in order: 'Chrysalis', 'Metamorphosis', 'Transmutation', 'The Red Kimono' and 'The Ephemeris Protocol'.