At the start of the film, a group of rich brats are shown driving their imported Mercedes at dangerous speeds in a drunken state during late hours. As they are driving, they come across another similar youngster drink-driving. They engage in a verbal duel and subsequently race with their cars. At one curve the youth runs out of his luck and loses control of his Land Cruiser and consequently crashes into the foot-path.
Cut to Uttar Pradesh District court where an advocate Suresh Vashishth (Brijendra Kala), who also doubles as an astrologer, gains a client - who seems to be a thug waiting for bail - by saying that his current Lawyer Girdhar Sharma has a habit of forgetting the names of his client and joking that he might even get him a death sentence instead of a bail.
Enter Jagdish ‘Jolly’ Tyagi (Arshad Warsi) a Defence lawyer who attempts to get his client, Dr. Harphool bail on the pretext of the judge’s birthday and states that media fabricated the entire incident involving Dr. Harphool's son operating a pregnant woman for the sake of a Guinness Book of World Records entry. Mahesh Gupta, the PIL filer opposes this by showing the photos taken with Dr. Harphool’s cell phone furthermore accuses him of using his clout to suppress a case from being registered. Upon hearing this Dr. Harphool loses his cool and in the ensuing chaos unintentionally admits that his boy operated the woman. Due to this false move, the judge postpones his bail along with Jolly’s salary.
Disappointed with the result of his latest case Jolly loses hope in Meerut and decides to move to Delhi, the capital of India, in search of a better clientele where his Brother-In-Law lives even after much persuasion by his friend Sandhya (Amrita Rao) to remain persevere.
But the situation gets even worse in Delhi where Jolly, in order to make a living, poses as an apprehended terrorist in front of the media for Rs. 1000. While in Delhi, Tyagi comes to know of the Land Cruiser Hit-and-run case involving Rahul Dewan, son of Billionaire Yograj Dewan (Mohan Kapoor), whose defense lawyer is the much respected ‘star’ litigator Tejinder Rajpal (Boman Irani). During the trial, the strong Rajpal brings to light the fact that 7516 road accidents occurred in Delhi, while the newspapers of the past 6 months only seem to highlight the occurring of 1 accident. Thus, Rajpal successfully gets Rahul Dewan acquitted due to lack of evidence, eye-witnesses and the so-called ‘Land Cruiser’, claiming that his client was being victimized by the media due to the fact that he was from a rich family.
In the aftermath of the court judgment, Jolly, after being inspired by the media backlash, takes a leaf out of Advocate Mahesh Gupta’s book and files a PIL in the court regarding the case. When Judge Tripathi’s (Saurabh Shukla) questions the filing of a PIL despite the issuance of a sentence earlier, Jolly, along with Vasu (Ishtiaq Arif Khan), mentions media reports about the police presenting tampered facts and leaving out critical evidences. He gets a rescheduling of the hearing after getting rebuked for failing to provide evidence, citing media reports and for making spelling mistakes in the PIL like ‘apple’ instead of ‘appeal' and ‘prostitution’ instead of ‘prosecution’.
Jolly, heartbroken after the incident, stays back late. A person named Albert Pinto (Harsh Chhaya) approaches him, claiming to be an eye-witness who was present while the accident took place at the night of 20 April and who also saw Rahul Dewan. He provides Jolly with a copy of the police complaint he filed along with the ticket of the film after watching which he was returning to his hotel and testifies in the court. As a result the court asks Rahul Dewan to appear again. Jolly gains overnight media recognition and an office from Kaul Saab whose daughter was raped and murdered by a cop’s son but later walked free due to Rajpal’s exploitation of the loop holes present in the judicial system.
Albert Pinto Actually is Tejinder's man and wants more money from the Dewan's . Albert Pinto tells Jolly that he will turn against him and not identify in court saying that a deal has been stuck with Tejinder for 2 Crores and Jolly will get 20 Lakhs . Jolly tells Albert that he made a mistake and should have bargained for more. But he is baffled to know that Albert is Tejinder's man. He accepts the offer and tells Sandhya this who gets angry at him for not standing up for the victims and being selfish.
Kaul Saab comes to know the next day that Jolly has taken the money from Tejinder and slaps him. Jolly realises his mistake and decides to fight and win the case. He searches for evidence and with the help of his Brother in Law finds a video which has the recording of the day of the accident. Jolly presents this video in court and Tejinder somehow says that this was driven by the Driver of the Dewans'. Jolly does not lose hope and finds an eye witness but he is reluctant to come to court but tells him to stop searching in New Delhi and search in Gorakhpur where he will find the evidence.
The day of the hearing, Jolly questions SI Rathi whether he did the investigation honestly and diligently and asks him to read out loud the names of the 6 who died. Jolly claims that in reality only 5 people died and seeks permission to present the sixth one who apparently died as a witness without prior notice. Rajpal vehemently objects but Judge Tripathi overrules his objections.
A Burkha clad Sadakanth Mishra enters the court and recognizes Rahul Dewan as the driver of the Land Cruiser which killed his 5 acquaintances and rendered him a cripple. He also states that SI Rathi left him after taking his yearlong savings of Rs. 30,000 and gold ornaments meant for his sister’s wedding. Rajpal asks for a rescheduling but Judge Tripathi does not comply. During the lunch time, SI Tripathi calls Pinky to bring the man he captured, who turns out to be one Ramakanth Sukhla. When the court resumes, Rajpal claims that the police investigation was ‘botched’ up since it stated that 6 people died in an accident by truck while the prosecution claims that 5 died in an accident by a car. He recommends that the strongest action be taken against SI Rathi as evident from the Prima facie and questions whether the court should be sending Rahul Dewan to jail on the basis of a botched up investigation. He jokingly adds that foot-paths are not commissioned by Government for sleeping. Jolly, in his submission, agrees with Rajpal that foot-paths are not for sleeping and rhetorically asks why these poor, deprived of work, shelter and food come to tarnish the beauty of the metros. He adds, however, that they do have one right: the right to obtain Justice; one that is given to them by the Constitution of India. Infuriated, Jolly states that if the case lingered any longer, Rajpal would certainly prove that Sadakanth Mishra was Shah Rukh Khan while a train caused the accident, and due to lack of evidence the court would have to comply. He states that foot-paths are not for driving either. This was the 'joke’ and he adds that Judge Tripathi’s reputation was at stake. Judge Tripathi says that there are two aspects to the case. The first one was that SI Rathi was to be suspended with immediate effect and an investigative process be started against him. The second one was the manipulation of facts, which would be necessary only if Rahul Dewan was guilty. The judge dishearteningly admits that in spite of being fully aware of who committed the crime, he is rendered helpless due to the lack of substantial facts as evidence which are, as evident, prudently kept at bay by the ones whose interests are at stake. He also adds that he was determined to make this one an exception even if it meant exploiting his chair to some extent. He was least bothered to notice whether he would be set free in the impending legal battle. As a result, the court finds Rahul Dewan guilty and sentences him seven years of imprisonment under Indian Penal Code 304. Thus, Jolly wins the case and his self-respect and is congratulated by all and sundry.