1958年，瑞典第一批女警毕业，为数不多的女性先锋虽然象征国家在性别平等上跨出一大步，但在现实生活中，她们就连跨出一小步都无比艰辛，因为她们被迫穿着的裙子就像砂纸一般，时时刻刻摩擦着大腿。她们被民众讪笑，被媒体贬低，也被同事奚落。这批新警力被调到全国犯罪率最高的克拉拉警勤区，开始在斯德哥尔摩街上巡逻。但她们很快发现最大的问题不是罪犯，而是连同事和整个社会都抗拒她们。

　　At the beginning of the season Sylvia becomes pregnant with Andy's child. A baby boy, Theo, is born towards the end of the season. This is contrasted with the fate that awaits Sipowicz's older son, Andy Jr., who announces that he is to join the police force. Andy is finally bonding with his estranged son when he is gunned down, which leads the elder Sipowicz to fall off the wagon. Andy Jr's murderers are killed themselves by Simone in an act of self defense.
　　Bobby and Diane, whose relationship had been put on hold while she attended AA, resume their relationship only for Diane to begin drinking again when her abusive father beats her mother. Her father is eventually killed and her mother becomes the prime suspect.
　　James Martinez and new detective Adrienne Lesniak begin an affair but only after Lesniak tells Medavoy that she is gay, then that she is not; Martinez later breaks up with her due to her controlling and unpleasant behavior, and Lesniak eventually leaves the squad. Medavoy himself leaves his wife, recognizing that she is holding him back but it is too late to save his relationship with Donna who leaves to take up a job with Apple.