In the summer of 1968, the year of Prague Spring with a Cold War winter, Oxford students James Borthwick and Eleanor Pike set out to hitchhike across Europe, complicating a budding friendship that could be something more. Having reached southern Germany, they decide on a whim to visit Czechoslovakia, where Alexander Dubcek's "socialism with a human face" is smiling on the world. Meanwhile, Sam Wareham, First Secretary at the British embassy in Prague,...