Decrypting the Codes

This six part series takes you to the heart of a war that was fought out far from the bombs and shells of any battlefront.

The German Enigma machines were portable cipher units with a set of rotors to encode scrambled signals which were theoretically unbreakable.

The Purple Cipher was probably one of the most complex codes used during WWII.

This episode concentrates on the work of the code breaking activities of the then secret Bletchley Park.

The final part of this series covers the American and British efforts to protect their convoys.