Commissioner Nikolas Heldt starts his career in the Bochum police criminal division in a long-running human trafficking case, using unconventional methods to catch mob baron Felix Bricheaux, for which stickler chief commissioner Detlev Grün wants him suspended. State prosecutor Hinrichs protects him but dies from a cardiac crisis, his successor Ellen Bannenberg grants the suspension during in internal investigation. Felix walks from court after key witness Natalia Sokolowa, whose skin Heldt saved, fails to testify. Heldt gets Bannenberg to help find out what hold ...

When Heldt attends Bochum's first-ever happy divorce-party, this time in central Bochum's "Endlich frei!", he helps a woman who was nearly robbed. It turns out here's a wave of party goer-victimizing crimes, so suspects include her ex, a car thief, a drug trader, Tine Schütz who organizes such parties all over the Ruhr area and various nightclub staff.

Heldt's 'fatherly' publican and family friend Karl-Heinz "Carlo" Funke is found next to the corpse of his landlord Erich Baumann. Unlike commissioner Grün, Heldt is determined to prove his buddy's claim of innocence despite a violent money row the evening before. Autopsy shows poisoning by exclusive claret, hidden behind Carlo's cooler. Heldt examines dodgy third chess player Sven Lattbeck, and neighbor Dr. Paul, and is suspended, the clock ticking. Although evidence piles up, Heldt keeps examining the neighbors, with some risky help from Ahmed and unexpectedly from ...

Heldt and Security firm chief Michael Nickel's arrival when the alarm is triggered in Bochum's auction house chases the clever yet clumsy masked robber after a shot to stop chase by Auction master Stefan Mahlburg. Heldt doubts an insider job after spotting a thug at the Nickel house, who seems to scare gun owner Michael's teen son David more, and finds indirect indications the knave must be involved, yet fails to win his trust the boyish way. A second, successful robbery attempt ends in a fatal shooting.

Patrizia Sendel's corpse is a found by a pro playing a cop on a parking lot belonging to the fetish scene, unlike laborer Georg Sendel's wife. She was dressed way beyond their means, part of a lifestyle she also lacked any breeding for, despite Internet sales of worn lingerie. Heldt finds she even attended the city's exclusive country club, without the normal discretion around hunky 'pro instructor' Simon Scheuffele. The case is countered by supervising judge Decker who was client with both. Heldt also finds proof plumber Georg must have found out about his wife's ...

Tanking on the way home Heldt is just in time to control an exploding amateur bomb brought into the station by state of the art robot. *Grün fearing a test run, he and prosecutor Bannenberg focus on a lead to chemistry student Alan Barsani, who has a geocaching game alibi. Heldt believes it and makes a mode cars racing circuit friend, car crash-crippled Manuel Unterberg. Other club members like dubious cleaning firm manager Dierk Jager also make plausible suspects, but Heldt must face his buddy's accident's tragic shadow back to his single mother's home where he was ...