Half a year after he precipitously left the country to pursue a private investigation on Mallorca, Nikolas Heldt returns to resume his life. However the Bochum PD already replaced him with eager gentleman commissioner Ian Kramer, yet Interior minister Herbst wants the unconventional hero reinstated due to glorious results in Spain, Heldt even turned down a federal police job. Their new case is a masked home-robbery, the MO of serial criminal Dorn, whose lawyer now successfully petitions for a revision, during which several forensic errors occur. Heldt assumes it must ...

Commissioner Heldt is excluded by chief Grün from the current counterfeit medicine investigation and ordered to read up on old cases. Bored, he jumps even at the unpromising case of a death threat email to stickler bailiff Raimund Gerber, who soon after proves the victim of pranks and is shot in the shoulder. Heldt checks up on Gerber's gut suspect, law student Timo whose computer was seized, but moves on to Gerber's fired colleague Dieter, who bent the rules corruptly. By the way, Heldt stumbles upon college paper 'ghost writing' and a counterfeit drug circuit.

Achmed coincidentally notices the clients f his favorite kiosk across pub "Carlos" being held hostage by a gorilla-mask and alerts Heldt, who grudgingly sees the case assigned to a lame commissioner and cocky SWAT captain Schneider. Achmed identifies the kidnapper's voice, demanding a weirdly low and precise sum, as painter Klaus Fehrichs. Heldt refuses to standby aside and finds out the hostages also hide things.

Heldt eagerly volunteers to investigate at local SciFi convention Kap Kaminski the apparent prank out of control between the Licht brothers. But on top of a glued mask, follows an attempt at lethal arson, which the first victim couldn't commit. The only obvious alternative is autistic Steffen Kemper, who rarely speaks or takes off his Major Thomas costume, hoping his father will return from space, but Heldt hopes to communicate trough the boy's drawings and digs into the brothers' own fiery youth.

As administrative punishment, lout Heldt is assigned to dreary customs routine checks escort. However he stumbles upon art smuggle from Turkey. The case is complicated by the customs' refusal to cooperate. Heldt resorts to clever and sneaky tricks to access evidence. Meawnile diner manager Carlo is finally home.

A day after an abysmal performance at a police staff party, Rodolf 'Rudi Rastlos" Kern is found in his harden, fatally pierced by some missing giant needle. His daughter Sara reports two attempt in vain to steal the safe. Neighbor Jürgen Boll tolerated the terrible voice in his choir, former boss Alfred Königstein kept booking hi even after retirement. Late model beat cop \Walter Mertens's daughter Angela, also in uniform, keeps popping up. All of them harbor secrets potential motives.

*The Bochum public and Heldt to some extent sympathize with an elusive 'Robin Hood' robber known as 'red pullover' who distributes some of the lot from am-rmored transports. He's too wlel informed, so an inside job is presumed. Heldt however belives the clumsy latest job by firm IT man Dennis Storz is separate and works on a theory it's a similar robber from years ago, who was recently released from jail. Die Leute lieben ihn, doch Staatsanwältin Ellen Bannenberg steht unter Druck .

The prosecutor is appalled that her partner Stefan opens his next gallery exposition with the local 'gangsta' rapper, but the real horror is when he's fatally shot by masked underground rival 'CrayZee'. Heldt pushes his team to adopt hip-hop in order to investigate. Their rivalry proves rooted in competition for fame and profit, leading to the production team, and the potential scandal from a still unpublished text. However Heldt digs on to a contraband cover-up.

Someone is stealing works from collector-crazed photographer sisters. Heldt's police team and prosecutor Ellen Bannenberg have a hard time finding the link, except nerdy insurance detective Gernot Pütsch and her husband Stefan's gallery. Heldt smells a scam, confirmed when near-victim Heinrich Tiemann ends up admitting to his old friend, commissioner Detlev Grün, he's blackmailed with his family's safety, while others tragically lack that in the finale.

Due to his wife's illness, commissioner Detlev Grün is the third jury member in the final round of Bochum's annual inventors competition. Vanessa Kochlowski startles with a drone who recognizes and paralyzes picture-input-identified persons, but is goes berserk and electrocutes another juror. Heldt is delighted with competing teacher Lars Zieler's nostalgic 'big boy' tent and mentality, but can't ignore he had motive (the prize) and opportunity. So did Sven Lattbeck, an incorrigible small fraudster suddenly swimming in cash. Heldt however also focuses on respectable ...

At night, commissioner Grün runs over race prize dog "Flinker Difar", whose owner Sylvia von Gunten demands 125.000EUR damages, insurance investigator Frank Kaiser's company covers the other half. Heldt helps find out the canine died hound earlier, maybe murdered. At the dog's fancy funeral, Heldt spots suspects like blogging do rights activist Malte Üding, but he has a biology frat alibi. Heldt looks into competitor Hermann Huber, and crazy gambler Karl Bukowski, Sylvia's kennel trainer Willy McCloud, the rumor of a sheikh paying well to tip off which dog to buy.

Dutch commissioner Jan Kramer helped prepare a case against elusive Dutch corrupt contractor Ruud van Breukelen, but is rests on the testimony of terminally-ill accountant Klaus Conrad, who goes missing just before the trial. Prescutor Ellen Bannenberg and Grün must temporize while Heldt finds Conrad, but he's knocked down, yet finds the encrypted accounts, which weird super-nerd Arthur Brenner must crack. Klaus is killed just when Heldt finds him, but the corruption parties list changes everything.

Old-fashioned bug-buster Henner Bocht and two kid bystanders are injured when his trick is blown up with remote control. Although he won't hear of it, prime suspect is former trainee and now market-leader Seiffert, who uses modern equipment. Heldt also looks at the clients, including a senior tenant refusing to move out and fancy heirloom chef Nadja Liebknecht whose reputation was ruined by a cockroach report but hides an even juicier kitchen secret, and Mario helps find a pattern.

Cleaning firm of the year CEO Enno Dürkamm is fighting for his life in hospital, having drunk water from a detergent-poisoned bottle. The ward-winner exploited his staff ruthlessly and recently dumped his original employee Horst Falter. He isn't getting much more sympathy from bright loner stepson Ennos Till, who feels Enno ruins the business, just from girlfriend Silke Krauss. Single mother cleaner Anja Reberlein's fingerprints are found on the 'weapon'. Heldt works out the firm's employment actually constitute exploitation of illegals, but how and by whom?

Investigating the crippling fall from his balcony of pushed abusive husband Otto Renz, which is later confessed by wife Martha, Heldt gets convinced some vigilante is 'punishing' husbands with loose hands in several recent cases. Superior Grün dismisses his 'conspiracy theory' to concentrate on a counterfeiter gang. * Heldt pushes on 'informally' and as hard-handed pimp Kevin Kruppka is run over with his own car, concludes the MO indicates someone with police experience. Beat-cop Klaus Starcke's patrol was on site repeatedly, but failing to drink his junior partner ...

Several robbery-murders occur, the only link apparent being a cab company. Heldt is appalled to hear his buddy Ahmed, who drives freelance, is set up as suspect, but works out a connection with false testimonies and suspects an unfair competition motive, so he goes undercover as lure.

Heldt 'infiltrates' the teen schoolmates of Sina Maibaum (15) who attempted to kill herself after a mean social media campaign against her and finds the relevant circle is Marleen Kranzler 's popular hip-hop dance course. Cool lawyer's son Tom Reindl is leaned on to admit his part, but no evil mastermind. Sina's buddy Christine is found sickly jealous, like musical lead rival Lucy. Heldt's real priority however is an offer from the federal prosecutor to meet hired gun Anne Lerch, who can tell him who paid her to shoot his parents, but demands a lot, including her ...

After informant Anne Lerch was shot at home, commissioner Nikolas Heldt only hears her puzzling dying last word (later found squirrel in Spanish) and is kidnapped himself, chained in a decommissioned swimming pool, but still as determined to find out about 'the lawyer' who ordered his parents' murder, with due suspicion. Interior minister Uwe Herbst shows great interest and promises state attorney Bannenberg a promotion. Even chief commissioner Grün agrees to bend the rules when Achmed comes up with a way to clone Heldt's cellphone, allowing Karl-Heinz "Carlo" Funke ...