What's Wrong with Secretary Kim: It Was You All Along

SINOPSIS

Everything is pointing to Young Joon—that the boy Mi So is looking for is not Sung Yeon, but him. Mi So doesn’t really understand why the whole family of her boss is lying about his real identity. To confirm her speculation, she pays a visit to Young Joon’s mother and finds a clue that might lead to her childhood hero. Meanwhile, Young Joon figures out that somehow Mi So’s sisters are not going to accept him easily. To win their hearts, he joins Mi So’s family on their vacation trip.