The following version of this book was used to create the guide: Saint, Jennifer. Ariadne. Flatiron Books, 2021.

Jennifer Saint's novel Ariadne is written from the first person points of view of the main characters, Ariadne and Phaedra. The novel is written in both the past and present tenses. The following summary employs the present tense and adheres to a linear plot structure.

Throughout their childhoods, Ariadne and Phaedra, the princesses of Crete, have known that they have little autonomy over their own lives. When Ariadne turns 18, her father, King Minos of Crete, announces his plans to marry her off to Cinyras of Cyprus. Disgusted by the man, Ariadne begs her mother, Pasiphae, and her father to release her from the union. Neither one obliges.

Shortly thereafter, King Minos's annual supply of Athenian tributes arrives on the island. The Athenian youths are sacrificed to the sisters' half bull, half human brother, the Minotaur, each year. When Ariadne sees a handsome man amongst the tributes, she is convinced she is in love. She soon discovers that the man is Theseus, prince of Athens, and becomes desperate to save him.

Ariadne confers with the palace craftsman, Daedalus. As the creator of the Minotaur's imprisoning labyrinth, Daedalus is the only one who knows how to escape the maze. He agrees to give Ariadne the secret so she can help Theseus defeat the Minotaur and escape Crete.

Although Theseus promises to take Phaedra with him and Ariadne back to Athens, he and Ariadne leave Crete without her. The new lovers sail for the nearby island of Naxos. After they spend the night together, Ariadne wakes up horrified to discover Theseus has abandoned her.

Meanwhile, Phaedra waits and waits for her sister and the prince to appear on the beach. Theseus has given her the wrong beach on purpose, thus abandoning her in Crete. Phaedra soon learns that Theseus escaped and that Ariadne is dead. The only way for Crete to make peace with Athens is to marry her to Theseus.

Ariadne is about to let herself die of starvation on Naxos, when the god Dionysus arrives. He thanks Ariadne for caring for his home. Over the following weeks and months, the two become close and fall in love. Although Ariadne is initially reluctant to trust Dionysus after what happened with Theseus, he convinces her that he is different from other men and other gods. The two soon marry and start a family together.

Back in Athens, Phaedra is becoming increasingly stifled by her life with Theseus. He is not only brutish and braggadocios, Phaedra soon learns that he is deceptive as well. Not long later, she discovers that he lied to her about Ariadne's fate and that her sister is still alive, living on a nearby island, and married to a god. She longs to visit her sister, but cannot leave home because of her two children.

Phaedra soon falls in love with Theseus's son, Hippolytus. She travels to Naxos to seek her sister's protection should she and Hippolytus run away together. When Ariadne discourages her from this plan, Phaedra flees the island in a rage.

Ariadne travels to Athens, determined not to abandon her sister a second time. Not long into her visit, Phaedra confesses her feelings to Hippolytus, who refuses her. Realizing that what she really wanted was freedom, Phaedra hangs herself.

After her sister's death, Ariadne returns to Naxos. She and Dionysus then venture to Argos, where Dionysus's brother, Perseus, lives. The brothers argue over whose people should serve which gods. The dispute soon results in a battle, during which Ariadne dies.

Ariadne is immortalized as a constellation. From the sky, she not only gets to watch her children grow up, but becomes a source of hope to women all over the world.