Reeftown is in danger! The inhabitants of a coral reef are threatened when a shady real estate deal started by the greedy Groper floods their area with poisonous waste. Romance, mystery and intrigue revolve around the Seahorse Cafe, where the lovely Pearl Trout falls in love with Corporal Bert the Soldiercrab. But the beautiful coral reef is slowly dying and Corporal Bert is sent to find the source of the deadly poison. Will Pearl and Bert ever see each other again? And will they be able to stop the greedy Groper from poisoning the entire reef? Find out in The Sign of the Seahorse by Graeme Base.