Sarah and Tim loved swimming – they were both in the school team, and went to the same diving club, down by the docks. Although only twelve, they both knew how to handle themselves underwater.
Sarah signalled to Tim that they had ten minutes air left in the tanks, and he looked back towards the boat to see that they hadn’t drifted too far. He saw the familiar blue hull of the ‘Pride of Dawlish’ above them, and gave her the thumbs up.
The pair swam into a new rock pile, enjoying the movements of the small fish and pointing to the different crabs they saw on the sandy floor below them. Tim glimpsed a cave ahead, and pulled Sarah by the arm to go and investigate. Once inside, they realised that it was cavernous, and soon needed their torches to see ahead. It was then that Sarah noticed their air was low, and they turned gracefully to return to the surface. They looked ahead – where was their tunnel? There seemed to be many where only one had been? How would they know which one to take? Their air was too low to investigate them all!
Seeing light, Tim swam upwards, and the pair appeared inside an enormous underground chamber – big as a stadium. The pair looked about them, open mouthed. They could not believe what they had found.