Kumaravel (Vijay Sethupathi) is a typical lower middle class youth who mainly lives in TASMAC bars. His friends and neighbors have nicknamed him Sumaar Moonji Kumar (average-looking Kumar), and he is crazy about Kumudha (Nandita), the girl staying opposite to his flat. It is a one-way love and her father (Pattimandram Raja) has sought the help of Annachi (Pasupathy), the local boss, to find a solution and teach Kumar a lesson. On a parallel track, another alcoholic Bala (Ashwin Kakumanu), a smart bank salesperson, is always under pressure from his boss Poochandi (M. S. Bhaskar) and possessive girlfriend Renu (Swathi Reddy). One night, the life of the principal characters gets entangled, leading to the climax.

Kaashmora uses black magic to conjure an ancient warlord and his queen. Hilarity and horror ensue.

The film starts with Inspector Manimaran (Vinoth Munna) taking the job of Don Junga’s (Vijay Sethupathi) encounter, along with Duraisingam (Rajendran). On the way to his encounter, Junga tells his story. Back in Pollachi, he works as a bus conductor and is in love with Thoppuli (Madonna Sebastian). He gets involved in a fight, which angers his mother (Saranya Ponvannan) as his father Ranga and grandfather Linga were dons. They also lost their theatre Cinema Paradise and had to sell it to Kumarasamy Chettiyaar (Suresh Chandra Menon). So his mother fears he will also become a don. Junga tells his mother he will not be a don and will retrieve their ownership of the theatre. He goes to Chennai with Yo Yo (Yogi Babu) and starts saving money towards his goal. He also leaves Thoppuli as she wants him to give her a luxurious life and gift her with 365 sarees for each day of the year. One day, Junga comes to know that the theatre is being brought down and Chettiyaar is planning to sell it to a foreign company. He goes to Chettiyaar’s house and gives him a crore to buy back his theatre, but Chettiyaar insults him. Junga challenges Chettiyaar that he will retrieve back his theatre. He decides to kidnap Chettiyaar’s daughter Yazhini (Sayyeshaa), who is in Paris, so he goes there with Yo Yo, but the Italian mafia group kidnaps Yazhini to release their leader, who was arrested by the French police. Junga tells Chettiyaar he has kidnapped Yazhini and fights with the mafia group to rescue her from them. Yazhini and Junga escape, and Chettiyaar agrees to give Junga’s family the theatre in exchange for Yazhini. Yazhini and Junga later get married.

The film starts in the 1980s. A young Shiva (Jiiva) is trained in the ancient Indian martial art Kalarippayattu by his grandfather (Prakash Raj) to be bold and brave and fight against all odds, especially all that’s evil. Shiva grows up with his grandfather’s words as his Bhagavad Gita. However, Shiva’s parents (Udaya Murthy (Jayaprakash) and Lakshmi (Lakshmi Ramakrishnan) want him to lead a peaceful life. Shiva gets arrested by the police after fighting with a law student Guna, who is in Gowri’s (Sentrayan) gang. Enters Priya (Shriya Saran), also a law student. She is the daughter of a police official (Babu Antony). She bails Shiva out and falls for him after seeing him fight for other people’s good. Eventually, Shiva too falls for her.

Anbirkiniyal, an ambitious young woman, wishes to ease the financial burden of her father, Sivam, with whom she shares a lovely relationship. But things take a horrible turn when she goes missing.