The family of the medusae are not only the most venomous ocean inhabitants but also some of the deepest divers. Medusae have been found as deep as 8.300 meters.
Their existence is paramount to the oceans. Many of the large migrations of fish and mammals would not be possible without the existence of jellies. They are a crucial part of the food chain, many fish feed on jellies and in turn mammals or larger migratory predators feed on fish.
The scientist Gerhard Jarms of the Zoological Institute of the University of Hamburg takes us on a journey into the exotic world of jellyfish. He is one of the most renowned medusae scientists in the world.
Our expedition begins in the northern Atlantic where we will find the mysterious periphylla. We will continue on to the Azores in the Atlantic. There we will search for the XY jellies that seek shelter in caves in rough seas. In the Pacific we will swim with the jellies in the famous Jellyfish Lake and last but not least we will explore some of the world's most beautiful coral reefs of western Papua. And at the very end danger lurks around every corner as we set out to search off Australia's coast for the fatal sea wasp one of the most poisonous ocean inhabitants.