Halla Bol was a movie released in 2008, directed by Rajkumar Santoshi and starring Ajay Devgun, Vidya Balan and Pankaj Kapur. The movie also showed a number of others stars in small cameos (no doubt leveraging the power of Rajkumar Santoshi based on his long history in Bollywood). So you have a story that seems to be inspired by the Jessica Lal case, but also shows the life of a film star who reached a high point through not seeing whatever was happening around him, and then saw something so shocking that it finally caused him to find his conscience and speak up about what he saw.
Halla Bol cannot be counted as one of Santoshi's best hits; when you have seen movies such as Ghayal or Damini or Ghatak, you really cannot put Halla Bol in the same league. It is still a good movie, although you wonder about why Vidya Balan took this role; and you come out of the movie with a realization that although Ajay Devgun was the lead star, if there was a role you would remember from the movie, it would be the role played by Pankaj Kapur. The movie is good in parts, especially near the end, but the first half does give a feeling of a slow buildup, and you can see similar speed and slow touches in other parts of the movie as well. The music of the movie was by Sukhwinder Singh, and you really don't see the music as matching the performance of the film, nothing really worth writing about.
From this point, the story of the movie is outlined, so if you don't want to know the story, don't go ahead from here.
The story shows a film star, Ashfaque (played by Ajay Devgun), a rags to riches story. He was a part of a street troupe, being run by Siddhu (Pankaj Kapur). Siddhu is a reformed dacoit, who is looking at his street plays as a way of highlighting important issues that the masses will see, and think about, and hopefully bring about some change (you know how difficult it is for that to really happen). But Ashfaque wants to rise high, and climbs the ladder to become a famous film star, with a new name, Sameer Khan. He is an accomplished actor, and is now settled with a wife Sneha (played by Vidya Balan).
However, to become successful, you do need to do make compromises, and he has made many; he becomes a part of the system, being a manipulator and part of the corrupt world, but one day, he gets a dose of reality when he is a witness of a horrible crime at a party, and that eventually brings him back to his senses. But can he take on the system and the powerful and get justice ?