The Doctor and Nyssa have landed on a devastated planet. They find themselves on a train in the midst of where a murder has taken place. The Doctor says they should separate, and he ends up in business class. He reads a magazine, carefully ignoring the two people in the compartment with him.
Nyssa, meanwhile, has made her way through several cars, and ends up in a garden car. She is accosted by three teenagers, Guillame, Burdine and Jennette, who threaten her with their tools until she explains that she's from off-world. They think she is here to help with their rebellion and take her to their sleeping compartment.
Back in business class, the Doctor is unable to deflect the attention of his compartment mates, Emiliege and Mellin Kinloch-Jones. She wants him to play Perfidy, but he manages to deflect the conversation and give them the impression that he is an inspector investigating recent suicides. They explain the train system to him. The planet was devastated long ago, and the trains are constantly running. The people on the train-cities never disembark; they are hoping things will get better.
Nyssa's new friends introduce her to their father, Mr Villeharduin. They explain to Nyssa the class system of the train and their need to reform the system.
As the train enters a tunnel, the Doctor sees a reflection of his face in the window — only it is not his current face, but rather his first incarnation's face. A Tunnel Wraith appears at the window and begins to break in. Emiliege and Mellin try to get the Doctor out of the compartment, but he is starting to realise that things are not what they seem.
The Doctor suddenly finds himself in a well-furnished room. A disembodied female voice speaks to him. The voice becomes a beautiful woman who introduces herself as Maya, a Psionosphere, or planetary computer. She created the illusion of the world with the train as an adventure for the Doctor and Nyssa. She wants them to stay with her forever. The Doctor is angry that she is deceiving Nyssa, but Maya, able to read the Doctor's surface thoughts, says that she is only doing the same thing he does for his companions.
The Doctor is unable to convince Maya that he doesn't want to stay. She finally threatens harm to Nyssa if the Doctor doesn't stay. She kisses the Doctor, and he promises to stay if Maya lets Nyssa go free.
The Doctor steps back into the illusion, congratulating Nyssa on helping with the bloodless rebellion. Nyssa sadly informs him that Burdine died in the rebellion. The Doctor tells her that he will be staying behind, and that she must be "the Doctor" now. He gives her the codes to remove his telepathic link from the TARDIS.
Nyssa, crying, enters the TARDIS and enters the code. She feels a flash of pain, and the Doctor is there in the TARDIS with her. He explains to her what really happened, and tells her that the codes her gave her actually strengthened his link with the TARDIS, allowing him to break free of Maya's influence.
The Doctor tells Nyssa that he left Maya with the illusion that he has stayed with her. Nyssa wonders if their leaving Maya is the illusion.
Meanwhile, Maya watches happily as the Doctor takes part in the illusion she gave him of escaping her. She occasionally wonders if his staying here is an illusion he gave her.
- Villeharduin reminds Nyssa of her father.
- The Doctor and Nyssa separately reminisce about Tegan.
- The Doctor sees his original face reflected in the train window.
- The Psionospheres were constructed by the Makers.
- The Doctor suspects the devastated planet might be Earth.
- The stories in Short Trips: The Muses are inspired by the Muses of Greek mythology. This story is based on Erato, the Muse of Love Poetry and Mimicry.
to be added