Soviet spy Donald MacLean and Tory cabinet minister Iain Macleod were both sons of the Hebrides, born in 1913, went to Cambridge University and both tried to change the world. Macleod implemented independence for the British colonies – but was hated by the Tory right. MacLean betrayed his country – but believed he worked for world peace. Cathy MacDonald reveals the forces that shaped these very different lives.