Ghost Station

In brief, this is a spy novel set in West Berlin in the early 60's just after the Berlin Wall was constructed by the Soviets.

Centering on a group of spies operating out of a station called the Cabin, Dan Wells does a good job of integrating the importance and regular use of cryptography in this high-stress time of the Cold War. The main character is a cryptographer who gets a little too deeply involved in operations as his boss suspects a mole in their group.

This was quick and fun. Well worth the read!