Do you want to live? Of course I do!

Just before she gets hit by a huge truck, Inseo Han, an ordinary South Korean woman who worked in a research lab, receives a text message offering her a special journey, new relationships, and opportunities for extra income. Determined to make it out of the situation alive, she accepts the offer and soon finds herself in the Raotwan Empire of Laseania as Duke Adrian's 12th fiancee candidate, Isella Derhen. Inseo has to act the role for an entire month in order to make it back to earth alive, but this job requires her to deceive not only a few nobles but the entire empire as well as the emperor. Not only that, but Duke Adrian demands that Inseo must never fall in love with him.

Meanwhile, Adrian, the duke and patriarch of House Beleskez, is in search of an adequate fiancee to avoid a royal marriage with the emperor's third daughter, Princess Kiersten. Though things would be very simple if the princess were to marry the duke's son, Prince Aslan, political strife complicates the situation and Adrian cannot simple turn down the marriage. Hence, he seeks someone who can act as his fiancee so he would have a justified reason to avoid the royal marriage until Aslan succeeds the dukedom.

Will Inseo win the deal and the opportunity to save her life? Can she and Adrian pull off the tremendous act without getting caught?