In 1936, paranormal abilities have broken through in the world as a slow, subconscious tide, brought to the surface by the suffering of the Great War. While Germany has worked for over a decade to weaponize these abilities, in England, research lags behind. It's now underway at an ultra-secret site, Monkton Hall. Among the test subjects is Kim Tavistock, a woman with the Talent of the "spill"--drawing out truths that people most wish to hide. When she wins the confidence of caseworker Owen Cherwell, he recruits her into an effort to expose the head of Monkton Hall as a German spy. Kim infiltrates the upper-crust circles of some of the country's fascist sympathizers. There she encounters dangerous opponents, including a charismatic Nazi officer in the intelligence arm of the SS, Erich von Ritter. Playing a perilous game of cat-and-mouse with him, she uncovers a Nazi plan that she is convinced involves an invasion of England. Eluding von Ritter, traitorous English aristocrats, and at times her fascist-leaning father, Kim hunts a deeply undercover individual with a mysterious power over cold and ice. No one believes an invasion of the island nation is possible, not Whitehall, not even England's Secret Intelligence Service. Unfortunately they are wrong, and only one woman, without connections or training, wielding her Talent of the spill and her gift for espionage, can stop it.