During one outing, the three friends see Zenia, a long-dead university classmate who had stolen, one by one, their respective beaux . The novel alternates between the present and flashbacks featuring the points of view of Tony, Charis, and Roz, respectively. Zenia has given each woman a different version of her biography, tailor-made to insinuate herself into their lives. No one version of Zenia is the truth, and the reader knows no more than the characters.
Their betrayals by Zenia are what initially bring the three together as friends and bind their lives together irrevocably; their monthly luncheons began after her funeral. The novel, like other works by Atwood, deals with power struggles between men and women; it is also a meditation on the nature of friendship, power, and trust between women. Zenia's character can be read as either the ultimate self-empowered woman, a traitor who abuses sisterhood, or simply a self-interested mercenary who cunningly uses the "war between the sexes" to further her own interests. One reading posits Zenia as a kind of guardian angel to the women, saving them from unworthy men. This proposition comes as the conclusion of Atwood's later short story, "I Dream of Zenia with the Bright Red Teeth", which features the same characters.
Atwood claims that of all the characters she has written, she identifies most "with Zenia. She is the professional liar, and what else do fiction writers do but create lies that other people will believe?"
In the novel's present, Roz, Charis, and Tony each individually confront Zenia in a Toronto hotel room, where she tells each of them that the men they'd been with got what they deserved, and gives various versions of her earlier staged death, each as implausible as the accounts of her life.
Canadian literary critic Brian Busby claimed in his book Character Parts: Who's Really Who in Canlit that the character of Zenia was based on journalist Barbara Amiel.