Humlaa is a story about Devkishan Sharma, a school-teacher in a small town in India, who lives with his wife and two sons, Bhawaniprasad and Shivprasad.
When Devkishan discovers that Bhawani has turned to crime, he asks him to leave the house. Shivprasad, on the other hand, struggles to find a job and eventually moves to Bombay.
Upon arriving in Bombay, Shivprasad learns that Bhawani has become a successful businessman. However, he soon discovers that Bhawani is actually a smuggler wanted by the police.
After Bhawani is shot and hospitalized, Shivprasad decides to take over his brother's criminal empire. However, when Bhawani recovers, he asks Shivprasad to go back home.
Feeling humiliated and enraged, Shivprasad joins forces with a gangster named Jagtap to teach Bhawani a lesson. Jagtap manipulates the brothers into fighting each other, knowing that only one of them will survive.