

The tower had appeared overnight, which was already annoying, but what made it truly inconvenient was that it had appeared right in the middle of the village football pitch.
It was tall and round and made of dark stone that nobody recognised, and it had no door and no windows except for one at the very top, which was so high up that looking at it gave you a crick in your neck. From that window, if you looked carefully enough and had good eyesight, you could just about make out a curtain twitching occasionally.
Someone was up there.
The village was very put out about the football pitch. The monthly match against the next village was in two weeks and the tower was sitting directly on the penalty spot.
Zeb, who was eleven and took football extremely seriously, was the most put out of all. He stood at the edge of the pitch on the morning the tower appeared with his arms folded and his expression the one his mother called his determined face and his sister called his silly face.
Beside him stood his two best friends, Cora and Phineas.
Cora was practical and read a great deal and had opinions about everything. Phineas was cheerful and slightly accident-prone and always had snacks in his pockets, which made him very popular on long days out.
"Someone is up there," Cora said, shading her eyes and looking at the window at the top.
"Obviously," Zeb said. "The question is why."
"The more pressing question," Phineas said through a mouthful of biscuit, "is how they got up there if there is no door."
This was a good point and none of them had an answer to it.
They walked around the tower three times. It was perfectly smooth all the way around, the stones fitted together so tightly you could not get a fingernail between them. There was definitely no door. There was no ladder either, no rope, no obvious way up or down.
"Hello?" Zeb called up at the window.
The curtain twitched. Then a head appeared. It was a girl, about their age, with an absolutely enormous amount of dark red hair that spilled out of the window and hung down the side of the tower in a long thick rope almost to the ground.
"Finally," the girl said. Her voice carried well, which made sense given how much practice she presumably had at shouting from heights. "I was wondering when someone was going to say something. I have been up here since Tuesday."
"It is Thursday," Cora said.
"I am aware," the girl said. "My name is Rosa. I am very bored and also quite hungry and I would very much like someone to get me down from here."
"How did you get up there?" Phineas called.
"Curse," Rosa said, as though this were a perfectly ordinary thing to say. "Old woman. Bad mood. Long story. Are you going to help me or not?"
Zeb looked at Cora. Cora looked at Phineas. Phineas finished his biscuit.
"We are going to need more information," Cora said.
"Fine," Rosa said. "But could someone throw me up a sandwich first? I have not eaten since yesterday morning and thinking is very hard on an empty stomach."