When Catriona Hurst learns that her sister Caitlyn is getting into trouble in her societal debut, she immediately goes to London to rescue her bold, younger twin. Discovering that Caitlyn has planned to force Laird Alexander MacLean into marrying her by stowing away in his coach, Cat sneaks inside MacLean's coach to dissuade her sister. But not only is Caitlyn not there; Cat gets trapped inside when the coach takes off! And it's not Alex MacLean who discovers her, but his brother Hugh, who assumes he's caught the scheming Caitlyn in his trap. By the time he realises he's gotten the wrong sister, Hugh also realizes that the innocent Cat will be ruined if he doesn't do the honourable thing and marry her. But even though heat burns fiercely between them, will they be able to move beyond their battle of the sexes to discover love?