Whales are attacking tourists in Canada and lobsters are suddenly deadly in France. The Swedish scientist Dr. Johanson discovers aggressive ice worms on the seabed that are multiplying at breakneck speed.
When Rahim and Charlie report a light phenomenon and a sound that Jess has recorded, Johanson travels to Shetland. They receive a warning that a tsunami is heading for the Atlantic coast of Northern Europe and Shetland.
The expedition to study the Yrr sets out for the Arctic, where a large number of Yrr signals were spotted. During a trip by submarine, Charlie Wagner observes a magical sight.
Johanson suspects that an unknown marine intelligence, which he calls Yrr, is behind all the results. He wants to contact the life form with a research mission and therefore asks the billionaire and entrepreneur Aito Mifune for help.
Cécile recommends stopping fishing off the coast and warning the population against using tap water. The ice worms are investigated more closely. Charlie returns to Shetland, where she reunites with her boyfriend Douglas.
