Rosalind Newbury is counting down the days until her wedding to the Duke of Marlow, a man she has only met twice. The marriage is more an agreement between two families and less a romantic connection between two hearts, but Rosalind becoming a duchess will elevate her family's status to dizzying heights. And the duke is a kind man who will care for Rosalind, even if he doesn't love her.

She only has three weeks before her life changes forever, and she knows exactly how she wants to spend her days. As a child, Ros was inspired by her adventurous Aunt Alice and created a list of ten things to do before her wedding day. So far, Ros has done none of them.

She is determined to tackle each item, though she'll have to accomplish them all in secret. After all, a soon-to-be-duchess is not usually allowed to bury treasure in the pasture, eat sweets all day, or learn how to swim. She enlists the help of her best friend, Liza, who brings along her cousin, Charlie, a prodigal son-turned-boxer who has come to the countryside to mend his reputation and learn how to be his father's heir.

Together, the three of them work to complete the list, and as each item is crossed off, an unlikely friendship blossoms between Ros and Charlie. The more time they spend together, the more Ros falls in love with this imperfect man and his good heart.

With the wedding looming, Ros must decide to either admit her romantic feelings for Charlie and risk her family's future, or keep her promise to marry the duke and start a new life as a noblewoman.