Johan works in tandem with the GSI organized crime unit to bring in a cadre of armored car robbers

约翰·福尔克在哥德堡警察特种部队GSI执行例行任务。在一名挪威卧底警察和一名哥德堡最重犯罪团伙的平民渗透者的帮助下，GSI正试图购买六支突击步枪，从而将其从街上赶走。但突然间，当一个新的未知玩家突然立即想要购买不仅是这些武器，还有更多的武器，包括穿甲弹时，一切都发生了变化。GSI意识到这不可能是任何普通的强盗。有人会在哥德堡街头发动战争。与此同时，约翰·福尔克的渗透者弗兰克·瓦格纳的情况变得越来越复杂，他渗透的团伙头目意识到自己的一个人向警方泄露了信息。

Frank Wagner goes deeper undercover to infiltrate Europe's most dangerous Mafia, the Russian-est, consisting of ex - KGB officers.

A car explodes in front of a primary school where GSI boss Patrick Agrell has just left his children. The event reunites Johan Falk with Leo Gaut, a former criminal restaurant owner who Johan put behind bars a decade ago.

Johan Falk and his colleagues at the GSI go after sex traffickers importing young women from the East and forcing them into prostitution.

Johan is a two-fisted Gothenburg cop who finds himself in a shoot-out with jewel robbers. After the smoke has cleared, one robber, shot by his accomplice, and an innocent bystander, are dead. Three witnesses, including Helen, identify thug extraordinaire Leo Gaut as being the dead crook's trigger-happy colleague. Gaut soon threatens the three witnesses, and only Johan, the badge-wearing hero, can save them.

It's been two years since John Falk and Frank Wagner broke their cooperation and Frank started working undercover with the police. Frank's search for Kevin crosses Johan's investigation and opens up a new collaboration between them - with the big difference that this time it's personal for Frank.

It's a beautiful day in Slottsskogen, Gothenburg idyllic city park, when suddenly the unthinkable happens - gunfire amidst all people. Two gangsters shooting game against each other and a large police operation starts. The conflict grows rapidly to involve several gangs from Gothenburg underworld. GSI switched to try to identify a new thread which proves to be both larger and better armed than any other. The only clue is a tattoo on one of the killed gang members.

GSI second in command, Sophie Nordh, flips gangster leader Seth Rydell and convinces him to infiltrate a rogue military group. For the first time GSI Chief Patrick Agrell realizes that he is using a ruthless psychopath as an infiltrator. Can Seth be trusted or does he have his own agenda?

Johan Falk's stepdaughter Nina has gotten in contact with her biological father, Orjan, discovering that he is in debt to an Estonian construction company in Gothenburg, leading to Nina's kidnapping.

A group of young robbers, specializing in robbing shopping center security guards, are raging through out Gothenburg. A robbery goes awry when an innocent passerby is killed. Ricky, the gang's young leader, tries to quickly find an expert who can clean the money of the dye pack that exploded while Johan Falk, and his colleagues at GSI, accelerate their hunt.

　瑞典某市国王路公寓发生一起入室凶案，弗兰克•瓦格纳出于自卫错手杀死持枪入室的歹徒，瞬间被推向舆论的风口浪尖。他带着妻儿找到了GSI的特警约翰•福尔克寻求帮助。与此同时犯罪团伙头目推测弗兰克可能是潜伏在圈子里的卧底，找到平素与弗兰克有贸易合作的商人赛斯，恐吓其散布消息重金悬赏捉拿弗兰克的人。紧接着一名GSI女警员无故被枪击致使昏迷，更令案件陷入重重谜团。警察当局威胁弗兰克接受不平等契约，不然便要令他成为全国通缉犯。弗兰克愤怒出逃。随着五年前一宗击毙犯罪分子的案件重新被想起，真相渐渐浮出水面，人们口中的杀人嫌犯弗兰克原来真是为警察当局兢兢业业的卧底，也就是传说中的“代号丽莎”，可他终究难逃亡命生涯……

Falk is blackmailed into smuggling a truckload of guns from Latvia.

When Johan and his colleagues are watching Seth and his gang member Jack, they stumble on a larger case than they expected. Seth is selling arms to terrorists, but without Jack's knowledge, in a car where Johan's old colleague Pernilla mysterious appears. While Johan begin researching what Pernilla and SÄPO is doing, Jack suspects that everything is not right with Seth and that he's working with the police.

　　约翰福克在海牙欧洲刑警组织工作五年后，回到哥德堡加入瑞典警方精英部门GSI特别行动小组，打击各种犯罪组织。 他成为一名卧底线人的接头人，在北欧地区打击罪犯、军火商、贩毒者和卖淫团伙…

The police station is locked down. A snitch is compromised. Drastic and unexpected events take place. Both inside and outside the police station.

The unknown, large mafia organization is now showing its true face. The pressure that GSI and John Falk and his family have put on the organization, makes them fight back on all fronts. The rule book is thrown out. But to go after Johan Falk's family and trying to kill his wife could be the biggest mistake the organization has ever made. GSI closes up around Johan's family and the final battle begins ...

After the book became a success, the creator confirmed that there will be a movie out of it.