As beautiful as it may be, their friends' country estate is not where Lady Vespasia wishes to spend Christmas with her new husband, Victor Narraway of the London Special Branch. He seems to be hiding undercover dealings with the other guests, and spending too much time with beautiful Iris Watson-Watt. What Vespasia can't know is that Iris has a sensitive package for Victor that could unmask a traitor—nor can he stop thinking of another case 20 years ago, when he failed to protect a young Frenchwoman holding a secret message.