‘ABCD’ is about a capable dancer, who is provoked by the evil design of his employer. He naturally proves his mettle and emerge as a winner!
After having a bitter disagreement with his friend and manager Jehangir Khan (Kay Kay Menon) about the latter's blatant abuse of power and influence to win a dance competition called "Dance Dil Se" for his team JDC (Jehangir Dance Company), the choreographer of the dance company, Vishnu (Prabhu Deva), quits his job. At first he wants to return home to Chennai, but his friend Gopi (Ganesh Acharya) persuades him to stay in Mumbai with him. One day, he observes several young men using parkour to evade the police. They turn out to be protégés of Gopi, but despite their obvious raw talent, they lack the discipline required to become serious artists; they demonstrate this disastrously at a local event for a politician, wherein they set the stage on fire. After witnessing the same young men showing their dancing abilities at Ganpati Chaturthi to beat their rival neighborhood, Vishnu decides to start his own dance group with them; ultimately preparing them to compete in "Dance Dil Se". However, the lack of discipline among the dancers and the rivalry between the two factions in the group lead by D (Dharmesh Yelande) and Rocky (Salman Yusuff Khan) leads to multiple creative and emotional blocks. Initially, only Rocky and his gang are willing to attend the free classes, but soon D and his friends gravitate towards the studio.
They are soon joined by Chandu (Punit Pathak), a troubled but extraordinarily talented man suffering from a drug addiction, Shaina (Noorin Sha), a "bar dancer", and Rhea (Lauren Gottlieb), a Westerner who was JDC's star dancer until Jehangir tried to sexually assault her during a "private instruction". While Rhea immediately becomes the new star of the company, Shaina is harassed because of her profession. Despite teasing from his peers, Chandu demonstrates a great deal of respect for Shaina and defends her in front of the class and the pair quickly fall for one another.
Despite repeated pleas for peace in the studio, the two main gangs continue to clash, driving Vishnu to his wit's end. However, the students seem to improve and as a reward, he gives them money to buy new speakers, but they nearly lose it all when Rhea takes them to an elite dance club and challenge the resident champions, a professional dance crew called "Fictitious Crew". Vishnu arrives at the last minute and wins back the money, but while his students gain new respect for him, he is furious with them. After some hard apologizing, he forgives them and they return to class with greater discipline and drive, only to suddenly be thrown out on the street after D's father calls the cops. During all of this Rocky and Rhea start to fall for each other whilst D burns with jealousy. The community complains that their children should not be mixing in such a way and only through an impromptu dance performance are the youth able to convince their families of the importance of their talent. Only D's orthodox Muslim father refused to accept that his son desires to be a dancer.
The crew head to Dance Dil Se and audition, but when Rocky and D fight onstage for Rhea, their chances of appearing on the show in the first place seem bleak. Jehangir, in a bid to humiliate Vishnu publicly, persuades the judges to take the "Dhongri Dance Revolution" crew on as a "comedy act". Faced with ridicule and the idea that they are a joke and not true dancers, Vishnu asks Rocky and D to do a step that requires a great deal of trust for both, but they cannot muster the trust to manage it. Vishnu has them choose the people they would trust to perform the step with, but then tricks both dancers by blindfolding them and having them attempt it again; this time, they are successful, and the two factions begin to trust each other and work together. Not long before the finals, Chandu prepares to propose to Shaina, but he meets his old drug dealer on the street.
Now completely free from the hold of drugs, he refuses to fall back into that world, but the dealer, irritated, knocks the ring intended for Shaina into the street. As he retrieves it, Chandu is hit by a truck and killed, leaving the team devastated. Shaina, though barely able to stand from grief, becomes the centerpiece of the team's semi-final routine, in which they express the loss of their friend, bringing audience members to tears. The team and the community come together to bury Chandu, and DDR resolves to continue in the competition in his memory.
At the finals, Jehangir pulls a dirty trick: his informant Mayur (a performer in DDR but, tempted by Jehangir's offer of a main lead role in JDC began to feed information to the opposition) has ordered his dancers to copy the rival team's choreography and performance concept. Faced with losing, DDR crafts a new routine on the spot, based around Lord Ganesha. Their heartfelt and spontaneous performance reminds the cold-hearted Jehangir why he and Vishnu started JDC in the first place and is humbled as the DDR crew are rewarded with thunderous applause and victory in the competition.