The changeling - Robin Jenkins

Thirteen-year-old Tom Curdie, the product of a Glasgow slum, is on probation for theft. His teachers admit that he is clever, but only one, Charles Forbes, sees an uncanny warmth in his reticence and his seemingly innocent smile. So he decides to take Tom on holiday with his own family...But can a holiday that begins with swimming in the sea and playing cricket on the lawn really end as happily? Forbes' wife Mary is unconvinced, concerned her own two children may feel left out and that Tom is hiding something. Is he just quiet and misunderstood or is it something far more sinister? When accusations are made and the police involved, the real Tom is finally revealed.