A graffiti on a gigantic canvas at the Brandenburg Cathedral depicts the police chief in a rather unfriendly pose. However, a harmless prank by teenagers quickly turns serious when one of the spray painters is found dead. Commissioner Manzetti is assigned to solve the murder and is horrified to discover that his own daughter is part of the graffiti crew. When the hot-headed Manzetti is suspended from duty, he begins his own investigation, aided by a gifted computer hacker and an ambitious journalist. Above all, the forensic expert Bremer proves to be a helpful friend. Confronted with the brutal methods of ruthless criminals on one hand and the ghostly summons of his Italian mother on the other, Manzetti tries to save his daughter Lara from deadly danger. "Havelgeister" is the fourth installment following "Havelwasser," "Havelsymphonie," and "Haveljagd.".