Khaali Haath revolves around Mashal aka Mishi (Aiman Khan), who is a gifted, beautiful, sensible and high-spirited girl. Her elder sister, Sobia (Kiran Haq) receives a marriage proposal from Basil's (Ali Abbas) family. Mashal was out of town at the moments of commitment session. Basil sees his sister-in-law, Mashal, for the first time on the occasion of the engagement ceremony and instantly falls in love with her. He becomes obsessed with Mashal and develops an ultimate desire to attain her at any cost. Despite being her brother-in-law, he usually throws clues and indication that he is interested in her. Mashal finds herself in a miserable situation due to frequent harassment attempts from Basil. Mashal soon receives a marriage proposal from Haisam (Shahzad Sheikh) and Basil starts plotting diabolic schemes against this union. He misguides Mashal by showing her uneven closeness between her husband, Haisam and her younger sister Umaima (Faria Sheikh). And she thinks that Haisam is also trying to trap her sister just like Basil did with her. She starts talking rudely with her husband. Basil set a trap for Mashal's younger sister, he employed a man in Haisams office because Umaima had start working with Haisam in his office. The man tries to flirt with her and he succeeds. Umaima realizes that he loves her but Haisam warns Umaima that he is not good for her but she refuses to listen. The man take her to his home and decided to do Nikah right now. But Umaima refuses so he blackmails her. When their Nikah is going to happen, Haisam arrives instantaneously with police and they arrest the boys. Umaima apologies to Haisam and he takes her to his house. When Mashal sees them together, she wrongly blames Haisam and says that he kidnapped her and further. Everyone was shocked and heart broken Haisam slaps her in anger and goes to his room. Umaima told her all the story and she realizes her mistakes. On the other hand, Sobia hears Basil conversation about fake marriage certificate she confronts him due to which he slaps her and in anger he tell the truth that he love Mashal and wanted to marry her not Sobia. He locks Sobia in the room and later apologies to her but she shocks him by saying that if your daughter look likes Mashal then what will you do? Mashal apologies to Haisam and feels guilty and Haisam forgives her so the family becomes happy but when Sobia comes to their house crying everyone was worried she tells the truth to her mother and that Mashal listens and says her sister not to keep quiet. She tells everything to her husband about Basil's harassment. Haisam angrily leaves the house and Mashal calls Basil says to leave the house as Haisam has known everything and that he is going to beat you but Basil kills himself with gun when Mashal last time rejected his offer of coming to him.