A fearless Highland warrior. A disgraced noblewoman. And a betrayal that could destroy Scotland itself.

Callum MacDonald has earned his name across the Highlands as the Red Blade—a ruthless warrior whose loyalty to Robert the Bruce is matched only by the fury he unleashes on the battlefield. Reckless, battle-hardened, and feared by his enemies, Callum has never failed to claim victory … until the day he storms a Highland stronghold and finds no army waiting behind its walls. Instead, he finds Aisla Fraser.

Abandoned by her cowardly father when he fled before the coming battle, Aisla is left behind as little more than a discarded burden. Born in France to a French mother, she has never truly belonged in Scotland, and the secrets surrounding her past have made her father eager to see her forgotten. Widowed under scandalous circumstances and cast aside as ruined goods, Aisla has learned to survive in a world that sees women as bargaining pieces in men’s wars.

Taken captive by the fierce Highland warrior who conquered her home, Aisla refuses to bow to Callum’s authority. Proud, sharp-witted, and far braver than the father who betrayed her, she quickly becomes far more dangerous to Callum than any sword.

But when whispers of treason spread through the Highlands and evidence points to a conspiracy far greater than a single craven laird, Callum and Aisla are forced into an uneasy alliance. With enemies gathering on every side and Scotland standing on the edge of war, they must uncover the truth before betrayal destroys everything Robert the Bruce has fought to build. Yet the greatest battle may lie between them.

Because the longer Callum fights beside the woman who challenges him at every turn, the more he realizes strength alone will never be enough to protect what matters most. And to claim a future with Aisla, the Red Blade must become something far greater than a warrior. He must become a true guardian of the Highlands.