A silver bell will tell you the way.
A candle’s wick will hide you.
And a CROOKED SIXPENCE will be the first warning…
Time is running out.
When Ivy Sparrow’s grandma Sylvie is rushed to hospital, Ivy and her big brother Seb cannot imagine what lies in store for them. Returning to Sylvie’s house, they find it has been ransacked by intruders, a floating feather has left a mysterious warning scratched into the wall and two police officers in peculiar uniform are on the doorstep waving...toilet brushes. Pursued by the officers, Ivy and Seb take the only escape on offer: jumping into a suitcase wielded by a strange boy who claims to be able to save them.
Suddenly they find themselves in the incredible city of Lundinor, a market beneath London where uncommon people trade in uncommon goods: belts that enable you to fly; yo-yos that turns into weapons. But Ivy and Seb soon find out that muckers (as commoners like them are known) aren’t welcome in this hidden world and with the revelation of a family secret as shameful as it is incredible, they realise that there is much more to Grandma Sylvie than she – or anyone - knows. With dangerous uncommon people closing in fast, and with a terrifying uncommon alarm clock counting down to the deaths of their parents, Ivy and Seb must find a way to get out, get home and get their parents and grandmother to safety before it’s too late.