Set in 1745, as Bonnie Prince Charlie's rebel army marches south into England, "Midwinter" tells the story of Alastair Maclean, one of the Prince's most loyal supporters. Sent on ahead to carry out a secret mission of great importance for the Jacobite cause, Maclean is befriended by two extraordinary and very different men--Dr. Samuel Johnson, an impoverished tutor and aspiring man of letters; and the shadowy figure known only as 'Midwinter.' But England in 1745 is a land awash with double-dealing and betrayal, and, as his enemies close in on him, Maclean uncovers evidence that there is a traitor at work, someone so close to the Prince that no one suspects him.