The story is based on Aditya Kumar, a famous actor who plays a very famous superhero on TV and acts in films as well. He lives in a nice village of sorts with his family, which consists of his wife, Priya, and two children, Kabir and Raima. He frequently tries to explain to his son that all cartoons are fake and that he shouldn't waste his time watching them. Kabir gets irritated, and one night tells him that he is a "fake" hero too, for his stunts are performed by doubles. Feeling humiliated, he leaves home and is soon kidnapped by the cartoons his son watches. They kidnap him because they overhear two people talking and saying that Aditya is a famous hero. This kidnapping is done through a series of underground mazes, tunnels, and sewers. On waking up, he finds himself in an animated world. A group of cartoons greets him, identifying themselves as "Devtoons," i.e., the good cartoons. They try to convince Aditya to fight Jagaro, a powerful villain, to protect their existence and save their king.

Aditya initially hesitates, but when a character from Toonpur named Bolly says he is a fake hero, he feels humiliated but then agrees to fight so that he can prove that he is a real superhero to everyone, and particularly his son. Aditya and his cartoon friends attack Jagaro's base, defeat the "Toonasurs," i.e., the evil cartoons, and save the King, Tooneshwar, but in the process, many of their friends get kidnapped by Jagaro. Now the only option left for Aditya is to get the "Toonastra," a pencil-and-eraser-shaped overpowered weapon from Rubdoot (the supposed God of Destruction in Toonpur), and erase Jagaro from existence using its tremendous strength. He goes to meet Rubdoot, where it is discovered that Rubdoot is a hardcore fan of Aditya as a superhero. Aditya manages to get the Toonastra; however, Rubdoot warns him, saying that he can use this weapon only once, the reason being that this weapon needs constant charging, and Rubdoot himself is the charger. Aditya leaves, promising Rubdoot that if the weapon worked, he would make Rubdoot his best friend. This makes Rubdoot emotional, who promises to wait as well.

However, Jagaro gets to know of the plan concocted by the Devtoons and kidnaps Aditya's family to prevent his own demise. However, Aditya challenges Jagaro to a game- a final fight. Jagaro agrees, and the game starts at his gaming club. Aditya manages to complete the first level, which is wild-west themed, by rescuing Priya from the Toonasurs and destroying them. In the second round, Priya plays a pivotal role in crossing the traps successfully and saving Raima and the Devtoons with her ingenuity. Jagaro uses many methods of cunning and deceit throughout the rounds to prevent Aditya's victory. The third round is the final duel between Aditya and Jagaro, which Aditya manages to win after a long struggle. Afterwards, Kabir finally accepts his father as a real hero, which finally makes Aditya happy. Rubdoot is given Aditya's autograph and becomes his best friend. The end of the movie shows Aditya leaving the Devtoons in peace and Toonpur in a joyous celebration.