The story of Gunaah revolves around an honest lady police officer, Prabha (Bipasha
Basu). A lonely woman, she takes upon herself of cleansing the corrupt system by
being a part of it. Her life takes a dramatic turn when she meets Aditya (Dino
Morea). Prabha falls in love with Aditya when, while chasing him, she is about
to fall off a rooftop. Without a thought, Aditya saves her life even though he
knows that he would be arrested in the process. This incident leaves a lasting
impact on her mind and more so when Aditya refuses to explain his actions in the
lock-up as well as in the court.