The Secret Kingdom by Matt Drummond

6.40

Verity and Peter’s trip to the old family mansion takes a turn when the floor of their room suddenly gives way and they fall into an underground chamber where they are met by a civilization of creatures. The leader tells them that Peter's arrival was foretold as he’s the one who can use Great Clock of the Citadel to restart time and destroy the Shroud, a malevolent creature who feeds on fear itself...