A dark force has woken in the British Museum and stopped time, freezing London and its inhabitants. Will and Jo are the only humans unaffected by the spell, and have been fighting alongside London's statues to locate the source of the disruption. But now their statue allies have been frozen too, leaving brother and sister alone and pursued by murderous dragons. What is more, they have noticed that the unmoving people of London are getting colder by the hour ... No longer able to rely on London's statues for help, Will and Jo must stop the source of the evil before the life force of London's inhabitants drains away.