A rare white flower is delivered to a man whose name is not revealed to the reader. The man has been receiving a flower, always pressed, in a simple frame, and mailed by an unknown person, every year on his birthday for the last 44 years of his life. He is now 82. After receiving the flower, the man calls Detective Superintendent Morell, who has been following the delivery of the flowers since they mysteriously started arriving. After hearing the news, the detective contemplates the longstanding mystery. Morell has nothing to say when the recipient of the flower calls him and informs him of this latest delivery.
After receiving the flower, the recipient contacts a botanist who informs him that the pressed blossom is a rare flower native to Australia, known commonly as Desert Snow. The flower has no significant medicinal or hallucinogenic qualities, although the plant is considered sacred by aborigines. The recipient hangs the flower on a wall where he has hung all the other lovely and rare flowers, and he begins to weep.
The prologue directs the reader's attention to three key characters: the flower recipient, the flower sender, and Detective Morell. While not much is said about the nature of the relationship between these characters at this point, they are all linked by the flower. The recipient and Detective Morell use the latest flower delivery event to reconsider the mystery and the truth it represents. Therefore, the theme that develops is one revolving around the need to know the truth and the lengths to which people are willing to go to obtain the truth. This question will continue to arise as the novel progresses.
All three of these characters are connected through the main symbol introduced in the prologue: the flower, Desert Snow. The detailed description given this flower — its lack of practical uses and its sacred place in aboriginal thought — suggests that the person sending the flower likely is aware of the flower's qualities. The recipient may look to these qualities as clues to the giver's identity and motive. By keeping Desert Snow's characteristics in mind, the reader can consider how the ritual presentation of the flower represents and accentuates the giver's character and his/her relationship to the recipient.