Lady Behind the Mask

Kung is a graceful, beautiful woman who has grown up in the slum, with a mysterious background about her birth. Due to employment obligations, Kung finds herself travelling to Kheha Nang Khoi which is located on a cliff.
She is employed as a caretaker for a mentally challenged woman who wears a mask all the time. Kung later discovers that the lady is not crazy and may be related to precious lost jewelry, "The Pink Diamond".
(Source: ThaiDramatic_update; edited by Soju at MDL)