The Invisible Duchess

Elara Vance is a ghost in the ballrooms of Mayfair. Known as the "Invisible Wallflower, " she has spent years fading into the shadows of potted palms to hide her family's looming ruin. But when her father gambles away their last shilling, Elara is forced into a desperate gamble of her own: a marriage of convenience to the most feared man in England. Arthur Sterling, the Duke of Ravenwood, is a man made of gears and granite.
They call him the "Beast of Ravenwood, " a brooding recluse obsessed with steam engines and iron rather than society's glittering games. To claim his massive inheritance, he needs a Duchess who won't ask questions. He offers Elara a cold, clinical contract: fifteen thousand pounds, a shared address in the North, and a strict "no-touch" clause. But as the carriage wheels turn toward the wild, limestone cliffs of Derbyshire, the parameters of their agreement begin to fail.
Beneath the Duke's icy exterior lies a brilliant, tormented engineer-and beneath the wallflower's lavender silk hides a strategist with a mind sharper than any blade. As Elara begins to assist Arthur with his secret inventions, the "Invisible Duchess" becomes the only thing he can see. From the soot-stained mines of the North to the treacherous courtrooms of London, Arthur and Elara must fight to protect a legacy that is being sabotaged from within.
But in a house built on secrets and stone, the most dangerous innovation of all is a heart that refuses to follow the rules.