Sang Nang Prai

Maythawadee and Maythawalai are sisters who love the same guy, Phakinai. Maythawadee sets a plan to send her sister to marry the king of another land to get rid of her because she knows Phakinai loves Maythawalai. During her departure, a storm hits the boat Maythawalai is on and it sinks it. Phakinai tries to protect Maythawalai, however, both of them drown together. Maythawadee's spirit was then caged underwater. She watches and protects any antiquities that fell from boats and kill people who are coming to steal. Maythawalai is then reborn as the daughter of a colonel who studies archaeology.
(Source: ThaiDramaticUpdate Facebook)