The cover tells you all you need to know about this story for 9-12-year-olds. It's an animal adventure for older, thoughtful readers which moves and inspires without sentimentality.  

Hayley and Hero have both experienced loss and isolation, but together they create a bond, helping each other through their grief and, in their mutual trust and belief, they solve a diamond robbery!

Hayley's dad was a police officer, killed in the line of duty a year before. Her mum is trying to keep things together but is working hard in her catering business, and Hayley feels alone and sad.

A visit to the police station to catch up her dad's former work colleagues causes Hayley to meet a former police dog called Hero. He is due to be adopted out of the force after his handler retired early. No one has been able to befriend Hero, until Hayley - so her mum agrees they might adopt the dog.

It does take a little time for the dog to feel happy in his new family but soon Hayley understands his needs and encourages elements of his past training. Then, when a diamond is stolen at a private catering event, Hayley and Hero become a formidable force in tracking down the culprits. 

This is an intelligently written story presenting something of the amazing skills and empathy of animals with their owners. I loved it!