The Bletchley Circle

Seven years after WWII, four former female Bletchley Park codebreakers return to their crime-solving past. Susan, Millie, Lucy, and Jean team up once again to find the killer.

Susan investigates the victims' whereabouts to narrow down a list of suspects. Elsewhere, Jean and Lucy suspect that the wrong men have been convicted for a series of murders.

Susan finds a coded message in her home with Cavendish's address that unveils more clues that may ultimately lead her into the killer arms.

Former Bletchley Park colleague Alice Merren is awaiting trial for murder. Despite the overwhelming evidence of Alice's guilt, Jean is determined to prove Alice's innocence.

The circle's investigation uncovers three men with chemical burns in a truck crash in Salisbury plain and the team suspects a high level cover-up involving the Alice's trial.

Millie helps Alice get a job, but when she suddenly disappears and the police won't help, the women take the investigation into their own hands.