Teen Bahuraniyan - moving into the ghost zone

This typically has not been seen before. There are not that many prime time serials in the past that have brought in a ghost / spirit into a hindi serial that appears on real time, but Teen Bahuraniyan on Zee TV has done that now (maybe their TRP's were going down). Other serials in the past have used the concept of a ghost, but have later explained this as the tactic of someone to scare another person, or to get them to reveal the truth.
In Teen Bahuraniyan, the spirit is of Kaajal, and she appears to possess Bindiya (who has otherwise been shown to be a very sweet but also the least intelligent among the bahus of the house). So, Kaajal suddenly would take over Bindiya, with the objective of defeating her own sister, Payal, who has just entered the house as a new bahu. Of course, in the serial, the expectation is that everybody in the house will believe Bindiya when she makes all sort of allegations against Payal (maybe because she has been a member of the household for a long time).
The only time when you can be sure about Bindiya still surviving her independent spirit is when a mandir or some puja is involved, in which case Kaajal has to leave Bindiya, and then the Bindiya who comes back cannot understand what all is happening. And of course, other people in the house are not able to understand either.