In the smoky, tumbledown north of a sprawling city, where governesses duel with umbrellas and the gap between poor and rich is vast, lives a young lad called Barnaby Grimes. Dapper, self-assured, and handy with a sword-stick, he races around the roofs of the city – ‘highstacking’, as it is called – running errands as a ‘tick-tock’ lad. He is messenger, courier, assistant and researcher, always ready, and always ahead of the clock. He knows the quickest routes across town, which puts him (literally) streets ahead of the rest. If only London produced such ‘clerks errant’, instead of the be-studded and be-headphoned ilk that populate our streets…

Barnaby narrates the story with a winning and cheeky charm – he has an eye for pretty shop assistants, and has a genuine concern for his fellow man: he loves his city, from the gleaming spires of the financial district to the brawl-filled gloaming of ‘the Wasps’ Nest’, and would