The Long Way Home (The Southwark Saga #3)
Jessica Cale

Having left his apprenticeship to serve King Charles as a spy, Jack Sharpe is given a mission that may just kill him. In the midst of the Franco-Dutch war, he is to investigate rumors of a poison plot by posing as a courtier, but he has a mission of his own. His childhood friend Alice Henshawe is missing and he will stop at nothing to see her safe. When he finds her in the company of the very people he is meant to be investigating, Jack begins to wonder if the sweet girl he grew up with has a dark side.
When a careless lie finds them accidentally married, Alice and Jack must rely on one another to survive the intrigues of the court. As old affection gives way to new passion, suspicion lingers. Can they trust each other, or is the real danger closer than they suspect?