A story of family, friendship and mystery from one of the UK’s best-loved writers. When Scarlet’s grandma goes into a retirement home, she must sort through her belongings in the cramped flat above a shop in Crouch End, north London.

Here Scarlet comes across a real treasure: a novel that Gran wrote, imagining the life of a girl just like Scarlet, who once upon a time lived in the flat and worked in a cake shop downstairs.

But as Scarlet reads about Ruby’s life in Victorian London, she begins to realise this is no piece of fiction – Ruby was real!

A real life, facing real danger – and a mystery that unravels to the present day.