Rose Code. Kate Quinn. 2011.

1940, Bletchley Park, Buckinghamshire.

Three very different women - aristocratic Osla, Londoner Mab and shy local girl Beth - are recruited to the mysterious Bletchley Park, where the best minds in Britain train to break German military codes. 

1947, London

Seven years after they first met, on the eve of the royal wedding between Princess Elizabeth and Prince Phillip, disaster threatens. Osla, Mab and Beth - their friendship torn apart by secrets and betrayal - must race against the clock to crack one final code before it’s too late, for the, and for their country.