While her professional minder and procurator Gregor Cassell reports senile crone Hanni Haffner missing, she bugs Wilsberg in his bookshop. Accompanying her home, Wilsberg and Ekki find there a corpse: friendly colleague PI Erwin Zylla. Commissioner Springer's wheelchair-bound busybody niece Merle's computer skills help Overbeck research. *Wilsberg suspects greed motives for Gregor Cassell and Hanni's next of kin cousin Guido Haffner, who hires Alex to claim guardianship in court, successfully opposing Guido's daughter Vanessa Balders, who hired Zylla , and her husband Marcel. Next Gregor Cassell is found standing over Guido Haffner's copse, yet Hanni Gregor trusts only him. Wilsberg, Ekki and Alex must find the key in a dark family past, but time runs out.