Secret doors in the school library

Olive sat in the library with her nose in a book about volcanoes. She liked to read during breaks, because then no one disturbed her. But today was different - next to her sat Filip, whom she had never spoken to before. Philip was new to the school and gave the impression that he was looking for something. - Have you ever heard of a secret cupboard in this library? - he whispered. Olive looked at him with interest. - Is there a secret cupboard here? - Apparently so,' Filip replied mysteriously. - I saw it yesterday. The door at the end of the bookcase with the encyclopaedias. It looked completely different from the rest. Intrigued, they decided to see if Philip was telling the truth. They quietly shuffled between the bookcases, avoiding Mrs Irena, the librarian with the falcon eyes. At the very end, they saw an old wooden door with a brass handle, hidden behind a tall tower of books. It was narrow and had a tiny window through which it was impossible to look. Philip grabbed the handle. The door creaked and swung open a little. A quiet rustling sound came from inside, as if someone was turning the pages of a book.... Or whispering? - Maybe we shouldn't go in there? - Olive's whispering grew quieter and quieter, but curiosity won out. - 'I'm a bit scared, but we have to see it,' replied Philip and pushed the door wider. Beyond the threshold they could see a spiral staircase leading downwards, illuminated by a flickering white light. Olive and Philip looked at each other, their hearts pounding like mad. Suddenly, from the depths of the staircase, they heard a sound like the echo of someone's laughter.... They took the first step towards the mysterious passage, not knowing whether they would be in another part of the school in a moment, or whether they would....