Mistress Spy — Pamela Mingle

A determined sister . . .
Madeleine Vernon's dreams should be filled with elegant gowns and marriageable men. Instead, she dreams of avenging her brother's death. But when she's captured by the queen's men, she's forced to become a spy by her mysterious yet undeniably attractive captor.

A rakish spy . . .
After years of working for his father in Queen Elizabeth's service, Nicholas Ryder is close to going his own way. But now he's got a feisty beauty he must protect or risk her execution as a traitor to the crown. She's a distraction he can't afford, but he also can't stop thinking about her.

A dangerous lie . . .
It is Nicholas's job to foil plots against Elizabeth, and he sends Maddy into a household of suspected traitors to garner what information she can. As the line between captor and prisoner blurs, deceit, betrayal, and desire become a perilous mix. Ultimately, Nicholas must decide whether duty to the queen is more important than winning Maddy's heart.

Each book in the Spies in Love series is STANDALONE:
* Mistress Spy
* Game of Spies