Spain threatens to invade England, and the people of Plymouth are understandably fearful. They watch for enemy sails on the horizon, and worry about spies and traitors in their midst. But one person in the city already knows how events will unfold, and she has more on her mind than a potential invasion.

A tear in the curtain of time has stranded Alexandra Barton in 1588, with no idea how she got there or how to return to the present. If that weren't enough, she has to decide whether the handsome adventurer she encounters on Midsummer Eve is a spy, a murderer, a figment of her imagination – or all three. He may hold the key to her safe return, but will she be the same person when she arrives back in the present day?