Flash Marriage, an Army at the Door

A decorated war hero is summoned home by his powerful father, ordered to live as a commoner and find true love to inherit the family empire. After entering a contract marriage with a spirited woman, he brings her home for New Year's Eve, unaware his father is secretly testing his new bride. But when a ruthless rival collides with foreign invaders to seize his wife and destroy the realm, can he protect the woman he loves before the clock strikes midnight?