Alia Bhatt appeared as the small Reet Oberoi.

The song "Mujhe Raat Din" in the movie has the tune copied from the song "Mujhe Dekh kar aapka muskurana" from the movie "Ek Musafir Ek Haseena (1962)".

Karisma Kapoor was offered the lead role.

Bollywood remake of Jonathan Demme's The Silence Of The Lambs (1991).

The film was previously titled " Andhera".

Ajay Devgan was signed for the film but opted out.

Shah Rukh Khan was offered the lead role but he refused to work with the director of the film Mahesh Bhatt since his previous two films with Bhatt's production house, Chaahat (1996) and Duplicate (1998), were box office disasters.

Ashutosh Rana's famous evil scary screaming/yelling scene was used as background music in the TV serial Sankat Mochan Mahabali Hanuman.

TV Actor Rajeev Paul was signed for Akshay Kumar's role.

The name of the male lead character that is Aman Verma is same as the name of the actor who played the role of Reet's (Preity Zinta) boyfriend.

Most heroes did not want to sign the film due to Preity's role being bigger. Akshay was going thru a very bad phase in his career so he agreed to do the film. Most who had seen his work vowed he would win the best actor award. Preity would always say this in interviews. But Vaastav released and Sanjay Dutt ended up winning .

Hungama (2003) - Pari (Nadeem Shravan) derived from "Dil Ka Qarar" from Sangharsh (1999) (Jatin Lalit).

Sangharsh (1999) - Mujhe Raat Din (Jatin Lalit) copied from "Mujhe Dehkhkar Aapka Muskurana" from Ek Musafir Ek Haseena (1967) (O.P Nayyar).

Remake of a Hollywood thriller "Silence of the Lambs" starring Anthony Hopkins.