Ek Hasina Thi is a crime thriller drama. The movie revolves around Sarika (Urmila Matondkar). She is in love with a rich man named Karan (Saif Ali Khan), who is extremely possessive of her. Things take a turn when Sarika is involved in looking after Karan’s suitcase, which was filled with firearms. Sarika is arrested and Karan convinces her to confess the crime, as he’ll make sure to get her a light sentence. Sarika complies but is shocked to receive seven years of jail without parole. She learns that Karan is involved with the underworld, and intentionally sets her up into this to mislead police. With the help of another prisoner, Sarika escapes the jail. She undergoes an inside-out change, changes her look, and sets out to take revenge on Karan.