Ho Gaya Dimaagh ka Dahi is a slapstick comedy. A dying father puts his sons into a situation where they undergo hardships of life, learn about relationships and understand the ground reality of life. Ishwar Singh Chauhan (Kader Khan) on the verge of death, asks his three sons – Harry, Inder and Veeru (HIV)to take care of the ‘haveli’ that he has left behind for them in a hope that this will help them become more responsible and better human beings. The drama and humor unfolds when they get to know one family already resides there and meet Mirza Kishan Singh Joseph (Om Puri) and his family. The cat and mouse race begins and while in trying to get back the ‘haveli’, they encounter different people from different walks of life.
When Mirza Kishan Singh Joseph shows his adamance of not leaving the ‘haveli’ and asks them to get out, HIV then get introduced by Masala (Raajpal Yadav) to Aashiq Ali Advocate (Sanjay Mishra), and Teeli Bhai (Razak Khan) who give them tips and tricks to get back their property.