Three young children discover a secret passageway hidden inside their castle library. As they explore their way down into the caverns below they discover they are not alone; horrible things live in the dark. Creepy crawling things are coming down the tunnel towards them. But this is not the only horror awaiting them. An imprisoned dragon still wanders the tunnels searching for a way out.
Overhearing the children discussing the tunnels the evil Gort hatches a plan to release the dragon and over throw the kingdom. Now the race is on between Gwen and her brother Edmund to rescue a princess, stop a revolution and avoid being eaten by the dragon and whatever it is slowly crawling down the dark passageways towards them. Slither slither slither....