"The Bletchley Circle" follows four ordinary women with the extraordinary ability to break codes, a skill honed during World War II when they worked undercover at Bletchley Park, site of the United Kingdom’s main decryption establishment.
Now in 1952, Susan, Millie, Lucy and Jean have returned to civilian life, keeping their intelligence work secret from all, including family and friends. A series of ghastly murders targeting women, however, re-unites the team as they set out to decode the pattern behind the crimes.
Episode One airs Sunday, September 15, 2013 at 10:30 p.m. - Susan, noticing a pattern in a string of London murders, contacts her old friends from Bletchley — Millie, Lucy and Jean — to try to identify the killer.
Treating the crimes like a code to be cracked, the women gather all available information and evidence and then, through a sequence of clever deductions, determine how the killer is finding his victims and where a missing girl must have been abducted. Can they reach her before the killer claims his fifth victim?
Episode Two airs Sunday, September 22, 2013 at 10:30 p.m. - When Scotland Yard dismisses the women’s theories, they realize it’s up to them to stop the killer before he takes his next victim.
They identify a suspect and use Lucy to lure him into a trap, but their plan goes badly awry and Lucy is assaulted.
Shaken, the women take a different approach, contacting former war department members. Susan plans to meet with a psychiatrist whom she believes has helpful information, completely unaware of the danger that awaits her.
Episode Three airs Sunday, September 29, 2013 at 10:30 p.m. - Susan tells the other women that she came face to face with the killer — and he let her go. It soon becomes apparent that he’s becoming obsessed with her.
Following the death of a former spy who had been helpful in identifying the perpetrator, the women consider whether to continue their pursuit, but they know if they don’t find the killer, he’ll move somewhere else and more girls will die.
Their investigation resumes. Cleverly planting false clues, the murderer leads Susan into a trap.
This series originally aired April 21 - May 5, 2013.