It’s about (i’m not sure) witch-sisters (I think a group of witches with different kind of powers) they lived years ago.
One sister is put in a box en put in the sea for 100 of years. All these years she dies (drowning) comes back to live and drownes again. Now she escapes and is very angry and wants revenge.
Also what I remember is 1 of de sisters is talking to a man at a brown cafe in a harbour with alot of old boats.