Top assassin Maya takes a high-priced contract to kill the powerful elite Cassian in order to treat her seriously ill sister, but the mission fails unexpectedly and her identity is fully exposed. Cassian hides a dual identity as Finn, the frail and gentle second young master of the Hayes Group. Saved by a young Maya ten years ago, he orchestrated the assassination attempt on purpose to draw her close and protect her. After the failure, Maya goes undercover in the Hayes family. She gradually falls for Finn, yet uncovers his true identity and finds that the family’s ruler, Victoria, is the source of all their grievances and conspiracies. In the end, the two join forces to expose the truth, settle their past feuds, and stay together.