To Tame a Rogue by Alexa Aston

A spy with a guilty conscience. A war widow who works for the government. Both united to bring down a ring of traitors…

To prevent her father from marrying her off to an elderly suitor, Lady Gemma Barton begs her childhood friend to marry her, devising a way for them to be found in a compromising position. Gemma weds Rob, who then departs to serve on Wellesley’s staff in the war against Bonaparte. Gemma’s new father-in-law soon has her working for the British government, deciphering enemy codes.
Burke Nicholson serves in the Peninsular War as a soldier and spy, using his charisma and charm to gather intelligence. After he’s rescued from being captured and tortured, Burke lives with survivor’s guilt, believing he did something to compromise his latest mission which got his partner killed. He returns to London to continue his spy work, where he is partnered with Gemma and tasked to find a group of traitors within the War Office. The trouble is that Gemma is the widow of Burke’s former partner. Not only did he get her husband killed, but Burke fears their dangerous assignment might also end Gemma’s life.
The pair fight their growing attraction to one another as they draw closer to finding the rebels trying to topple the British government.
Will Gemma ever be able to forgive Burke for his role in her husband’s death, and will Burke ever be able to forgive himself?