Description of book

I could hear Dennis talking to my ma. 'She was little,' he said. 'Little like me. But old. Older than you. Those words gave me a cold shock. I could see Dennis imagining fairies, but old ones?
When Bobby's mother moves the family into a rented house in the country, a neighbour tells him that a child was once murdered there. Bobby doesn't care. All he wants is to get back to Dublin and to resume his wild life there, stealing from the crowded shopping streets and racing stolen cars at night. But getting his old life back doesn't turn out to be so easy, and the longer he spends in the old cottage, the more convinced he becomes that something very strange is going on there. Was there really a murder? And if so, was it the one he has been told about?