For director Anurag Kashyap, recreating Mumbai of the early 1990s in his controversial film "Black Friday", about the events leading up to the 1993 Mumbai bombings, was one of the most difficult things to do.

The film is releasing Feb 9.

Kashyap had to keep a lot of things in mind-like there should be no usage of mobile telephones or such phones visible in the film. Even the hoardings and cars used were restricted to the 1993 set up. One will only find Maruti 800 or vans in the film.

"Since there were a lot of street shots in the film one had to be very careful, in particular of the hoardings and cars used in the sets," said Kashyap.

Based on S. Hussain Zaidi's book, the film is on the conspiracy behind the Mumbai blasts and give a detailed account of the planning, execution and back-end operations that went into it.

The blasts left 257 dead and 1,400 injured and also brought into the spotlight the mafia-terrorist nexus prevalent today.

Produced by Arindam Mitra, the film features Kay Kay Menon, Pavan Malhotra and Aditya Srivastava playing inspector Rakesh Maria, Tiger Memon and police spy Badshah Khan respectively.