Every step you take - Maureen O'Brien

George Fletcher works all week in a City firm, and at weekends helps his mother look after his mentally handicapped brother Kevin.
It's not an exciting life, until he encounters Alison.
He becomes obsessed with her, but she doesn't know he exists.
She does know Kevin.
Polly leaves an unhappy home and moves into a room at George's mother's house.
Alison becomes friendlier with Kevin, who is increasingly agitated, while George looks more and more ill.
His childhood friend, Detective Inspector John Bright is worried about him.
Especially when the body of a young girl in found in a nearby park...