Adam Brake, a brilliant young astrophyisicist, and his young son, Matthew are driving to the village of Milbury, in order that Adam can carry out some research work. Excited, Matt points to the landmarks as they approach the strange village, the hill, and the stone circle which surrounds the village. A moment of chill takes Matt as they cross the circle boundary. Suddenly, there is something in the road! Adam steps on the brake. It looks like a huge sarsen stone, just for an instant. The car stops just in time. It is the figure of a lady.

The lady in question is Mrs Crabtree, the housekeeper of the cottage where Adam and Matt are to stay while in Milbury. She shows them into the cottage, and asks about the strange boxes which had arrived the day before. Adam explains to her that they are scientific kit, and that he hopes to measure the magnetic fields of the stones in the village. Mrs Crabtree seems puzzled and shocked.

Matt sees a strange girl at the window of the cottage. He dashes out to find her, but she is gone.

Matt suggests that he shows Mrs Crabtree a painting that he has brought with him. The painting depicts a frightening prehistoric event with people in a circle turning into stone and a bright light beam shooting up into space. Mrs Crabtree faints when she sees it, dropping the tea tray she was bringing.

As they rush to revive her, a resonant voice greets them. It is Mr Hendrick, Lord of the Manor, and their landlord. He ushers Mrs Crabtree to fetch more tea, and she says 'Happy Day' to him. He asks what happened and they show him the picture. He seems agitated, and asks about it. Matt comments on the similarity between the painting and the landscape. Also there is a strange inscription:

Hendrick remarks how futile the statement is, 'I deny the existence of that which exists.' Adam sends Matt out to explore the village so he can talk with Hendrick.

At the door, he meets Bob, who invites him to come a bike ride around the village. As they ride off, a strange bedraggled poacher watches them through a telescope. Back at the cottage, Adam and Hendrick chat about Matt, and how he is coping with his mother's death. Hendrick makes strange comments on how they should stay on in Milbury indefinitely.

Meanwhile, Matt and Bob race through the village on their bikes. A truck appears to hit Bob, but when Matt opens his eyes, it has vanished, and Bob is unhurt. They go into the shop, and Bob gets them ice-cream. He puzzles over the way they say 'happy day' to each other. He meets the girl he had seen through the window earlier. She tells them that they need new people, and then runs off again. Bob explains that she is Sandra, and her mother runs the museum. Bob tells him 'she isn't a happy one'. Matt is puzzled.

Hendrick takes Adam over to the village pub and introduces him to Margaret Smythe, the curator of the museum. Hendrick toasts to 'old times, and new'.

Next morning matt arrives at the village school. He gets into a fight with Kevin Lyle, who explains that he had to check if he was human. Matt is still confused. 'Not one of them?' Kevin asks, pointing to the other children at the high table. Lessons begin, and Matt realizes that the standard of maths is way above even his head. The teacher gives Matt, Sandra, Kevin, and another boy Jimmo, some easier work. Matt is not happy.

Adam arrives at the museum to meet Margaret. She shows him the exhibits of the museum, and they talk about the possibility of ley lines in the village. Adam doesn't believe in them, of course, being a scientist. But there are 53 ley lines in the village, and there are 53 stones left standing.... Margaret admits that she is lonely in the village, since her husband died. She is glad Adam is there now.

Lessons over, the children come out of the classroom. Kevin sees on the noticeboard that he has been dropped from the football team. He is angry, and when Bob argues with him, Kevin thumps him on the chin. Bob seems unhurt : 'see? it didn't solve anything'

Back at the museum, Margaret and Adam talk about the stones, and about the barber-surgeon who had been found buried under one of the stones. Margaret asks him if he will... touch one of the stones for her, just to see if he's the kind of man she thinks he is. Amused, he goes out with her to the stones, and as he touches it his body is wracked with energy, strange images in his mind, and he flies through the air landing in a pile on the ground.

Meanwhile, Matt is riding home from school. As he approaches a gate, the old poacher jumps out and surprises him. He crashes his bike into the fence.

GO ON TO EPISODE 2