One Pearl for Half a Lifetime of Bones

After accidentally swallowing a deep-sea pearl, an adopted daughter gains the power to breathe underwater. Each use, however, turns her further into a fish. The second son of the Lin family forces her to dive for his inheritance scheme, until her jealous adoptive sister kills her. Both return to the day the pearl was found. This time, her sister swallows it first, unaware that she has stolen its curse along with its power.