Set in Hackney, the series depicts a 22-year-old Jane Tennison (Stefanie Martini) as she begins her career as a WPC with the Metropolitan Police Service in 1973. At a time when women were beginning to be gradually integrated into the police force, Tennison has to deal with sexism, as well as difficulties in her home life as her family disapprove of her career choice. Under the guidance of DI Len Bradfield (Sam Reid), the naive and inexperienced Tennison assists in investigating the murder of a young runaway, Julie-Ann Collins. Meanwhile, criminal Clifford Bentley (Alun Armstrong) is released from prison, and along with other members of his family are planning a bank heist. Links to Collins' murder threaten to expose the Bentley family's plans.
