Ishaqzaade depicts the passionate love story of two defiant, rebellious individuals. The Chauhans and the Qureshis are two political families whose rivalry and mutual hatred for one another goes back generations. Parma (Arjun Kapoor) is a good-for-nothing local enforcer, grandson of the patriarch chauvinist, Grandfather Chauhan. His grandfather often takes digs at Parma for being the useless son of his widowed daughter-in-law. This makes Parma try to prove himself worthy. Zoya (Parineeti Chopra), a practising Muslim who offers Salat five times a day, is the trigger-happy, hot-tempered, only daughter in a traditional Muslim house full of brothers, along with her parents. She desires to go into politics like her father, but this dream is constantly laughed at by her family since she is a woman.
When the local elections take place, Parma and Zoya’s canvassing efforts lead to a clash between them, which results in Parma being slapped across the face by Zoya. While Parma is enamored by Zoya’s fearlessness, Zoya is intrigued by his raw charm (including his inability to properly pronounce her name, calling her “joya” instead of the proper “Zoya”). They fall in love after an series of incidents bring them together, and elope; Parma converts to Islam and changes his name to Pervez. After marriage, Parma and Zoya consummate the marriage by having sex in an empty train. Afterwards, Parma reveals that he tricked Zoya into marrying him. He slept with her in order to take revenge against her clan, and repay the humiliation she caused him by slapping him earlier on. Zoya is left heartbroken and devastated, as Parma joins his family in a celebration of “becoming a man”. Zoya attempts to invade the celebration in order to to shoot Parma, but is intercepted by his mother, Parvati, who urges her to calm down. Parvati tells Parma that he must honour his marriage vows and do right by Zoya. Parma’s family come to know of Zoya’s presence in their home and in the heat of the moment, Grandfather Chauhan shoots Parma’s mother when she tries to defend her son and daughter-in-law from the bloodthirsty gang. Parma realizes his mistake and protects Zoya from being murdered by his family.