On the beach of Borkum, a charred body washes up in a rowing boat. The body is burned beyond recognition, but soon the identity of the deceased is confirmed: it is the successful East Frisian defense attorney Fokke Huizinga. The murdered man was on Borkum for a meeting of hobby Vikings. Was there a dispute among the Vikings that ended fatally? And what role does the obscure healer Jeremias Brock play? His followers seem to be falling into a kind of madness, and the wife of the murdered man is one of them. The list of suspects keeps growing, and island detectives Mona Sander and Enno Moll are faced with a mystery. When the case becomes a personal matter for Enno, everything threatens to spiral out of control.