Lady in Red

A couple, Ishaan and Prishita hosts a party in their house and Ishaan's cousin brother gets jealous and angry as Ishaan got all the money and a huge house where as he did not. While they are arguing in front of their guests, Prishita goes inside the house and later her scream is heard, they find a note telling them that Prishita has been kidnapped. Who kidnapped Prishita?