An irresistible alliance : a Cynster next generation novel / Stephanie Laurens.

With his older brother's betrothal announced, Lord Michael Cynster is freed from the pressure of familial expectations. However, the allure of his previous hedonistic pursuits has paled. Then he learns of the mission his brother, Sebastian, and Lady Antonia Rawlings have been assisting with and volunteers to assist by hunting down the hoard of gunpowder now secreted somewhere in London. Michael sets out to trace the carters who transported the gunpowder from Kent to London. His quest leads him to the Hendon Shipping Company, where he discovers his sole source of information is Miss Cleome Hendon...When Michael Cynster walks in and asks about carters, Cleo's instincts leap. She offers him a bargain. She will lead him to the carters he seeks if he agrees to include her as an equal partner in the mission. Horrified, Michael attempts to resist, but ultimately finds himself agreeing. Then she delivers on her part of the bargain, and he finds there are benefits to allowing her to continue to investigate beside him. But the further they go in tracing the gunpowder, the more deaths they uncover. And when they finally locate the barrels, they find themselves tangled in a fight to the death, one that forces them to face what has grown between them, to seize and defend what they both see as their path to the greatest adventure of all. A shared life. A shared future. A shared love.