Gambling Lion - The Pride of Lions, #1

Soldier and secret agent during the latter part of the Napoleonic wars when Wellington and the British army were endeavouring to help force the French out of Spain. He was handsome, charming and a lover of many women, but saddled with a wife he neither loved nor wanted. Nicholas de Bresancourt, Duc de Valenciennes, was a complex man of many talents, but also a tormented one. Memories of his horrific experiences as a small boy in France before he escaped from the Revolution continued to haunt him. London.
June 1812. He was carrying important dispatches from the British Army HQ in the Peninsula to the War Ministry in London and hadn't been home for a year. While waiting for confidential and urgent documents to take back to the Army high command, Nicholas de Bresancourt is ordered to meet an inscrutable gentleman in the innocuous-sounding Department of Information in Whitehall. Lord Ashcroft wants to utilise his talents to track down a dangerous French agent who has been causing trouble for those still battling Bonaparte across Europe, and has now turned up in Spain.
Meanwhile, Nicky also takes the opportunity to catch up with his adoptive relations, including the dying family matriarch, the nearest thing he's ever had to a grandmother, as well as the wife he was inveigled into marrying and now wants rid of. Unsurprisingly, being Nicky, he decides to take a few hours off for a bit of personal R&R from the stresses of family matters and work. Handsome, charming and a consummate lothario, he heads out on the Town with a few regimental friends and they take him to a new gambling salon in Mayfair which is all the rage: Le Lion D'Or, owned by a mysterious masked woman who calls herself La Lionesse.
Inexplicably fascinated by the lady, who in turn seems very taken with the rakish soldier, she asks him up to her private quarters to continue their game of cards and he accepts, and that's when she raises the stakes.