In The Firing Line - S2.E5

London's Metropolitan Police Dog Unit tests the skills of its leading specialist search dogs, pitting spaniels Diesel and Billy against each other as they hunt for hidden heroin. On the streets of north London, shift leader Pete Madden puts his Alsatian Brodie in the line of fire when they target two armed robbers, but as the trail runs cold they find themselves in pursuit of a gang of car vandals