Scientist Charlie Wagner discovers a phenomenon at an outpost in the Shetland Islands that fascinates professor Lehmann; abnormal behavior of whales off the coast of Vancouver Island worries cetologist Leon Anawak.

Dr. Roche informs a commission about the dramatic situation on the French Atlantic coast; Sigur and Tina return to the Thorvaldson to survey the seabed again for ice worms and find the worms have continued to spread.

Dr. Roche detects the same bacterium in crabs that have invaded coasts all over the world; Professor Lehmann has bad news for Sigur; Tina persuades Sigur to go with her to Geneva to check whether ice worms have also been found in other seas.