A performance created out of the fascination with the Baltic Sea and the underwater world full of unusual species of animals and plants. Together with the youngest viewers, we will go on a fascinating, full of secrets and unusual journey under water. Maybe we'll touch a porpoise, maybe we'll hear sirens, maybe we'll be even more delighted with the sea that we have at our fingertips. What stories can you hear when you listen to the sound of the waves? What is hidden in the depth of the Baltic Sea? Does the unknown always have to be scary, or rather thrilling and beautiful?