Kuch Khattaa Ho Jaay is a family comedy drama set in the town of Agra where Heer Chawla (Guru Randhawa) lives in a joint family along with his grandfather Brij Bhushan Chawla (Anupam Kher), elder uncle (Atul Srivastava), aunt Rajjo (Ila Arun), younger uncle (Paresh Ganatra) and an adopted brother, Chaman (Paritosh Tripathi). The family owns Chawla Sweets, a successful chain of sweet shops in Agra. Brij wants Heer to get married so that he can see his grandson but Heer is in love with Iraa Mishra (Saiee Manjrekar) who doesn’t want to marry as she dreams of becoming an IAS officer and needs to study to clear the exams. Iraa is forced by her mother to marry as her younger sister Pallavi, who's unmarried, is pregnant with her boyfriend Manoj’s child. On knowing Iraa’s predicament Heer sees this as a golden chance to marry Iraa. Iraa agrees but on the condition that she'll clear her IAS exams and only then will she consider starting a family. Iraa’s life turns upside down after marriage as has to handle household as well as office work. To avoid household chores Iraa and Heer announce that Iraa is expecting, thus not letting her work anymore. What happens next forms the rest of the story.