The Doctor and Peri have landed in the middle of a heat wave. As they walk through dry fields, they notice greenery in the distance. As they approach it, they see it is a village named Sair.
Peri introduces herself to the young man, whose name is Tablibik. After his tour, the Doctor declines a meal and heads back to Peri. However, after an hour of conversation with Tablibik, Peri wants to get away. She finds him vain and arrogant. She tells him she must find the Doctor and leaves. Angry, he conjures a demon and aims it at Peri.
As Peri looks for the Doctor, she starts to think more about Tablibik. The more she thinks about him, the angrier she gets at the Doctor. When she meets up with him, she snaps at him and suggests they stay in the village instead of going back to the TARDIS.
The Doctor and Peri walk through the village, and he explains what he learned, though Peri pays little attention, thinking mostly of Tablibik. They are surprised to see a group of women conjuring demons to break up rocks in the field. They head back to the inn to get some rooms.
In his room, the Doctor notices chalk marks on the floor. He sees Tablibik outside his window and watches as Tablibik conjures a demon that sends flashing light to the Doctor's door. He tries the door, and though it's not locked, he cannot open it. He is trapped inside his room.
Peri, waiting in the bar for Tablibik, is impatient until he arrives, then allows him to take her to his room.
The Doctor finds a piece of chalk and traces over the marks on the floor. It is a pentacle; the Doctor sighs in annoyance. He climbs out of his window and heads to the office, where he saw, on his tour, some books on witchcraft and devilment. In the office, he examines several books, but hears Papus and Rasphuia coming and hides. They conjure up a voice, which tells them the strangers are not of this time. The voice tells them to warn the Doctor about Peri, who could be easily corrupted. It tells them the Doctor is near, and as he tries to sneak away, he makes a small noise, revealing his hiding place.
In the morning, Peri joins the Doctor for breakfast. They go outside to explore, and Peri shows the Doctor what she has learned — how to conjure demons. He tells Peri she should return to the TARDIS, but she snaps at him. She runs back to the inn, where Tablibik is waiting.
The Doctor is in his room, making preparations. Peri comes to him to tell him she wants to stay. He conjures demons that will help to break the spell that Tablibik holds over her. Tablibik, however, conjures a demon that fights the Doctor. Peri wants him to stop, but he refuses, so she conjures a spell that will remove the demon. The Doctor then threatens to conjure demons that Tablibik, and he starts to run away in fear.
Papus and Rasphuia have heard the whole thing, and promise to punish Tablibik. Coercion is not their way. Rasphuia conjures a spell to help Peri heal.
- The Doctor has given Peri her own TARDIS key.
- Peri drinks alcohol and gets drunk.
- The Doctor casts a spell to break a psychic hold over Peri.
- The Doctor thinks orange juice is one of the best things about Earth.
- After Sarn, the Doctor took Peri to a moon.
- The stories in Decalog are linked by the story Playback, in which psychic Silverman examines various items in the stranger's pockets. For this story, he examines a piece of chalk.