During the precinct's open day, popular workaholic uniformed cop Frank is strangled right there. De Cock fears the killer may target the authorities in general rather then just the victim. The only obvious suspect among the guest is Frederiks, a member of the terrorist Veenman group. He actually has an appointment as informer with one of the cops called Jan, which puts the team on the trails of some suspected dirty cops cases, however De Cck dislikes considering the idea, which a reporter is eagerly spreading in the press. The widow Anja also reacts suspiciously according to the police therapist, who hints at confidential problems on Frank's side.
—KGF Vissers