In 1754, renowned maker of clocks and automata Abel Cloudesley must raise his new-born son Zachary when his wife dies in childbirth.

Growing up amongst the cogs and springs of his father's workshop, Zachary is intensely curious, ferociously intelligent, unwittingly funny and always honest - perhaps too honest. But when a fateful accident leaves six-year-old Zachary nearly blinded, Abel is convinced that the safest place for his son is in the care of his eccentric Aunt Frances and her menagerie of weird and wonderful animals.

So when a precarious job in Constantinople is offered to him, Abel has no reason to say no. A job presented to him by a politician with dubious intentions, Abel leaves his son, his workshop and London behind. The decision will change the course of his life forever.

Since his accident, Zachary is plagued by visions that reveal the hearts and minds of those around him. A gift at times and a curse at others, it is nonetheless these visions that will help him complete a journey that he was always destined to make - to travel across Europe to Constantinople and find out what happened to his father all those years ago.