Operaatio Valhalla

The Spiral expedition that arrived in the north finds something strange in the lake, which raises questions about the fate of the previous expedition. In 1991, Radilov believes that children have a tendency to recognize ruptures between different realities. Alina's husband Arno plays his own game behind Alina's back. 

Alina meets Saara, who has had a close relationship with her father. Saara helps Alina remember hidden things from 30 years ago. Alina also gets hold of Radilov's dictation machine and she hears her father's voice after a long time. begins to open up to him. Arno contacts the reporter to make an exposé about Spiral. 

Saara puts Alina into a trance and helps her see where Radilov once hid the sensors needed for the accelerator that can be used to travel to another world. 30 years earlier, Radilov gets into trouble with his research assistant Karpov. Alina gets a tip from a journalist with whom Arno has been in contact before the accident. Gunnar takes control of the nature conservation organization and the operation starts to get dangerous. 

Schneider and Brant are preparing an experiment where Alina is supposed to cross the gap between the two worlds. As he has already done exactly 33 years before. On his own, Radilov is preparing for a similar test that Karpov has forced him to take. Something is going though.