Phryne Fisher has decided on a holiday in Sydney, but no sooner has she gotten there that she is confronted by mysteries. The first is that Dot, her female companion's, sister has apparently disappeared, gone off without a word to her husband and leaving two young children behind. Dot is nearly prostrate with worry on behalf of her sister's children, who her brother-in-law is completely clueless about having to take care of, but he believes his wife has run off to be a streetwalker, and he labels both her and Dot "whores".
Phryne agrees to look for Dot's sister, and is soon after approached by two students at the Sydney University who ask her to look into another mystery. A safe at the college was somehow broken into, and a great deal of important papers were stolen, including the college's accounting books, the garnet jewelry belonging to the Dean's wife, an ancient Egyptian manuscript sent to the University to be translated, and an illustrated book of hours belonging to the Spanish Monarch, Juana the Mad. Apparently, an innocent student was blamed for the crime, and the two students are his friends who cannot believe that he is actually guilty of the crime.
Now with two different crimes to solve, Phryne is pulled in different directions. The case of the student must be solved before the next Monday, when the student will be judged by the Teacher's Council and expelled from the University. Although the young man professes innocence, the stolen exams were found in his study carrell. While some say this proves his guilt, others ask who would be so stupid as to commit a crime and leave evidence pointing to oneself as the culprit? Others still wonder where the rest of the items stolen were hidden, since only the papers and exams were recovered.
Phryne sends out word through the criminal grapevine looking for Dot's sister, while Dot and the local police comb through the hospitals and morgues. When they come up empty, it relieves Dot a bit to know that her sister is still alive, but she doesn't give up searching.
In the case of the student, Phryne uses her plans to dine at the college and go to games by its students and staff as excuses to investigate the goings-on and crime in the college. She discovers that many of the professors think that the student is guilty, but if he is actually innocent, they wouldn't know who to blame. Many dislike the Dean of the College, who is a mean bastard who likes to denigrate his fellow professors and those who work for him, discovering their secret and not-so-secret sins and lording it over them. Not quite a threat of blackmail, but it's enough for him to feed his sense of power over the others.
The student, she finds out, has been dabbling in the occult scene, and is mixed up with two very shady characters. Phryne contacts him directly and sees he fears the supposed powers of the two, one a tarot-card reader, the other a mesmerist. He was seduced by the female tarot reader, and now believes that the mesmerist can control him from afar, enough to kill him, or have him kill himself. Phryne is able to use her knowledge of the Golden Dawn ritual to be able to reassure him, as well as a little psychology, but attracts the attention of the two shady characters in so doing.
Then, Phryne discovers that Dot's sister has really been arrested in a raid on a whorehouse, but the whores all claim she was there to teach them deportment, and she is in jail under a false name, so her husband will never find out that she was there. She will be released soon, but Phryne and Dot must make sure her husband will welcome her back. And she still has to find out who burgled the safe and why... Can she do it before the trial on Monday, and discover who was behind the theft in the first place?
This was a book that was short, but enjoyable. Even though it is a fairly slender volume (for a novel), there is an awful lot of story packed into the pages, with a major plot, and several subplots that manage to be truly interesting and seem insoluble. The outcome is a very satisfying ending, and manages to include Phryne finding a new lover to keep her occupied whilst on vacation.