Episode one
The Earl of Manton and his family secure passage on the Titanic under a cloud of scandal surrounding his daughter, Georgiana. Meanwhile, there's tension between the English and American staff and crew man Jim Maloney attempts to smuggle his wife and children on board...

这是一部悬疑剧，虚构了四个拥有特殊技能的女人Susan、Millie、Lucy和Jean，她们曾帮助盟军提前取得二战胜利。
战争结束后，她们的生活渐渐平淡。一件凶杀案的发生，引起了她们的注意。

本季共4集，每两集一个案子。
Hattie Morahan饰演的Alice曾经也是布莱切利的一员，现在她面临谋杀的指控，马上要面临绞刑，Jean找回Susan、Millie和Lucy帮助Alice洗清罪名，却揭开了更深的内幕。
Susan离开英国前往印度，开始全新的生活，Millie却因为做黑市交易陷入了巨大的麻烦，甚至会有性命之忧……