And not just any bookshop. In 1893, Cole’s Book Arcade in Melbourne is the grandest bookshop in the world, brimming with every curiosity imaginable. Each day brings fresh delights for the siblings: voice-changing sweets, talking parrots, a new story written just for them by their eccentric father.When Pearl and Vally learn that Pa has risked the Arcade – and himself – in a shocking deal with the mysterious Obscurosmith, the siblings hatch a plan. Soon they are swept into a dangerous game with impossibly high stakes: defeat seven challenges by the stroke of midnight and both the Arcade and their father will be restored. But if they fail Pearl and Vally won’t just lose Pa – they’ll forget that he and the Arcade ever existed.

    Until the autumn of 1886, when five babies are left in outrageous circumstances: one in a tin toolbox, one in a coal bucket, one in a picnic hamper, one in a wheat sack, and finally, one in a coffin-shaped basket.Those babies were Lotta, Egg, Fenna, Sem and Milou; who were swiftly and firmly deemed 'the unadoptables'. Twelve years on the children still have each other - until the fateful night a most sinister gentleman appears and threatens to tear them apart. The gang decide to make a daring escape, fleeing the frozen canals of Amsterdam for an adventure packed with puppets and pirate ships, clock-makers and cruel villains - and with only a scrap of a clue to guide them to their mysterious new home . . .

    When the big day arrives, a series of very curious happenings lead to Anne being charged with an epic quest. Anne, Penelope, and new questing partner Hiro have only days to travel to strange new locales, solve myriad riddles, and triumph over monstrous foes--or face the horrible consequences.