Sebastian Winters’ father gets grumpy every Christmas, and this year it’s worse than ever. When Dad forbids Seb from touching the family’s grandfather clock, Seb seeks answers. Mysterious initials and notches carved in the clock, and a long-hidden letter, reveal that the clock can transport its inheritor, from the age of twelve, for one hour at a time, to twelve different destinations, on each of the twelve nights before Christmas. The twelve worlds are interactive and Christmas themed – and every kids dream.

But the clock holds another secret – one that could destroy Seb's family forever.