Wilsberg finally accompanies Anna on a holiday, to East Frisian island Norderney, but she brings along godchild Merle while Ekki and Alex mind the bookshop. Wilsberg and Merle, who teams up with Overbeck, can't help snooping when a motel guest is found with his head in the loo and Norderneyer restaurant waiter Gregor Schott, who refused to explain, is found dead on the beach, poisoned and clobbered. Chief commissioner Jan Brockhorst claims jurisdiction, but clueless island constable Grit Vierboom wants to solve the case with hobby sleuth Insa Scherzinger, the apothecary, soon meeting Wilsberg, Overbeck and Merle, so six detectives rival and collaborate in switching rapports to find motive and method among islanders, clashing on personal, business and environmental grounds.
—KGF Vissers