S1, E1: The first film explores the complex structure of the coral reef itself and the wildlife that lives on it. So vast it's visible from space, the reef is actually built by tiny animals in partnership with microscopic plants. It's a place full of surprises, always changing, responding to the rhythms of weather, tide, sun and moon. Within this magical and intensely crowded world we reveal how the amazing reef creatures compete and co-operate - from deadly fish-hunting snails to sharks that can walk on land, fighting corals and parrot fish that spin sleeping bags every night. Remote cameras, cutting edge underwater macro and digital time-lapse photography, have captured many sequences have never been filmed before, providing completely fresh perspectives on this extraordinary natural wonder.