Ngao Kammathep (2010)

Tien has been raised as a boy all her life because Kamontat, her ill-willed father, swapped her with the family's gardener/caretaker's son in his estate in Hua hin, leaving behind a ring strung in a necklace as key to her true identity. Before Grandpa Thaksasoot died, he declared that he wanted a boy to carry the family name since Thorn, her father's brother, who also later died, can't have children. Years later, Kamontat searched for Tien because he doesn't want his adopted son to inherit the money. Thorn and Rome were best friends and one fateful day, Rome met Tien and saved her from an unlikely situation; not knowing at first that she is a girl, brought her home and took care of her. Then Rome discovered Tien's true identity as the missing heiress to the Thaksasoot family fortune. Some years back, Rome was financially ruined by Kamontat. Driven by revenge, Rome kept the truth to himself but later admitted it and helped to get Tien back to her rightful place in the family.