When Baek Hayul wakes up in a foreign world as Duchess Aila Rinehart, she knows she has to escape. Her husband, Duke Claude Rinehart, is the antagonist of the story, “Prince, My Prince,” who gets executed for plotting a revolt against the crown. Hayul has no intention of dying alongside her new husband and demands a divorce. But when Claude turns down her repeated requests to end their marriage, she has no choice but to propose a deal. She gives Claude one month to win her love and change her mind, something she is determined to resist with all her strength, but her time with Claude leaves her feeling suspicious, restless, and uncertain. Will Claude be able to win Hayul over, or will they ultimately part ways?