Assassin Lovers

Plot Synopsis By DoramasQueen:

During the Republic of China, Feng Xiao, the adopted son of a wealthy businessman, and Lin Wan Xiu, the adopted daughter of a warlord, were married. But were assassins with hidden agendas. The two need to trust in love and resolve their misunderstandings and join forces to smash a conspiracy to sell national treasures.

(Source: Chinese = Douban || Translation = MyDramaList)