Two children, on holiday in Crete, are exploring the site of the palace of Knossos, home of the legendary Minotaur. The area has recently been hit by small earth tremors, but their visit takes place on a typically hot and sunny day. There is nothing to disturb the calm. Except that some of the passageways they revisit have changed. Flickering torches, a curious thread which runs along the wall, footsteps and an ominous shadow looming in the darkness are just the beginning of exciting and frightening encounters in the ancient ruins.