An educational graphic novel, which opens in an ancient cave, a "long-dead place, a moment frozen in time." A droplet from a stalactite prompts a reaction, a sword appears, and then stone crumbles and "a hundred forked tongues dart from desiccated jaws." Medusa reawakens. She takes the sword, and moves towards a set of stairs that have appeared: "the time has come to set things right. The action switches to a modern Australian English class, in which a teacher is explaining the concept of the quest story, and archetypal characters, such as the ‘typical Ancient Greek hero'", Perseus, and his quest to destroy Medusa. A modern Australian schoolboy, Brett, and his friend Rachel, leave school and go to a mysterious video-games arcade, run by a man named Kyron, which is launching a new video game, called "Medusa 3000". Putting on virtual reality suits, they play the game, where they find themselves in conflict with a cyborg Medusa, Medusa 3000. Embarking on a quest to destroy Medusa and save the kingdom of Cybertopia, they encounter the figures from the Perseus myth: Athena, the Graeae, as well as Cerberus, Orpheus, Charybdis, Tiresias, a Cyclops, and figures from other mythologies, such as Elaine, Arthur, a dragon, and Anubis and Osiris, as well as historical figures such as Cleopatra and Julius Caesar. With the advice of a beautiful goddess, who turns out to be the flip side of Medusa’s ugliness, they aid Perseus in destroying Medusa and then help the two sides of her personality merge. "We have both won. We have been given a second chance," says the now-merged goddess. Cybertopia is saved, and after kissing, Rachel and Brett leave the game for real life, though they are tempted to remain forever in the game, and the world of mythology. "For one day we were heroes", muses Brett, but Rachel doesn’t remember. Medusa goes back to sleep, leaving Cybertopia for the next set of players. 

Medusa 3000 is a portal fantasy for young readers, in which the protagonist travels into the classical past by means of a video game which brings Medusa to life. It is a form of reception in which science fiction and fantasy interact with classical myth. Explicit mention is made of Joseph Campbell’s The Hero with a Thousand Faces, and the story is structured as a hero’s quest. The portal fantasy gives modern Australian youth access to classical mythology. Its emphasis on multiple myths is characteristic of late 20th-century fantasy, which plays with many belief systems. Further, the emphasis on the hero’s quest is typical of this kind of young adult fantasy, which emphasizes the coming of age of the young adult protagonist. Medusa 3000 contains an afterword by the author, who shows how to draw Greek heroes and monsters, and discusses the importance of the "shadow figure," to his story. Medusa 3000 is published by John Wiley and Sons, in their Jacaranda series of educational texts for young readers, and is marketed to appeal to students enrolled in the Australian High School system; emphasis is laid on the appeal of graphic novels to reluctant readers, as an entry to classical myth and thought.