Denton's last remaining quarry is vandalised. Frost finds a baby in his office and is delighted to discover it belongs to DS (previously WPC) Hazel Wallace. He gets Hazel to look into some burglaries that have been occurring just after removal jobs have been completed. At the quarry a second body is found, which causes them to call the police. The only witness to the murder is an autistic boy, who immediately becomes a prime suspect. Frost finds out about some dodgy dealings in the past between the quarry owner and his former partner. The boy escapes through a window and the officers on duty get a severe telling off.