I'll try to roughly tell you. It's quite long and I missed a lot of episodes in the middle, since our TV was off for two weeks and when it came back, we had the Pakistan Geo which shows newer episodes than USA/UAE.
There is a family, in which there is a father, his son, Samar and his wife Roshni, his daughter Bebo, and the father's brother and his wife. The father is divorced.
A girl named Chandni, who has lost her memory, is brought into the house. Samar seems to be against this, and it is revealed that he used to love Chandni.
The father decides to get married to Chandni. Meanwhile, many strange events start to happen, and Chandni is very frightened.
They get married, and on the wedding night, Chandni goes to Samar, and reveals her true face. She says that she never lost his memory, and tells him to keep quiet or she will make him regret. (I don't remember the reason why
Chandni starts to torture Samar. Samar reacts to every little thing, and therefore everyone starts to think that Samar is against Chandni.
OK, here's the bit where I left off.
It is revealed that Chandni is really someone else, named Kiran. However, nobody realizes that she is against the family other than Samar. Kiran says that Samar has killed Chandni.
Bebo's fiance, Javed, sees Chandni, on the streets, really weak and being forced by someone. Kiran finds out about this and has him killed.
Samar is hiding from the police. Roshni, Bebo, and the others realize what Kiran truly is, but the father is still oblivious.
Bebo and Samar find Javed's diary, in which he has written about what he saw. They are sure now that Kiran killed him.
It is revealed that Kiran has kidnapped Chandni and is making her crazy.
Bebo tells the police that she is sure that Kiran killed Javed. Kiran is angry and threatens them all. Then she pretends to be leaving the house in front of the father, crying. The father is shocked when he learns about what Bebo has done, and shouts at Bebo.
Bebo says that when this stranger accused his son, he believed her, but now he doesnt believe his own daughter.
Roshni and Bebo fight with Kiran. Then Kiran asks Roshni who the person was who dropped her off.