A class trip to Borneo starts off with a bang - a trip to see a real-life volcano! But when the volcano unexpectedly erupts, Sam Fox is left behind with his ailing teacher, Mr Griffin. They make it down the mountain to the cool blue sea - only to be hemmed in by blood-thirsty sharks! With his trademark ingenuity, Sam finds a local boat, which is soon full of monkeys and chickens hitching a ride. As the sea boils and swells, Sam must fight off crocodiles, giant stingrays and real-life pirates, escape the erupting volcano and get Mr Griffin to hospital. Will they make it in time?