"Annaatthe" (2021) is a Tamil action thriller, directed by Siva, featuring Rajinikanth, Keerthy Suresh, and Nayanthara. Annaatthe, which is based in Tamil Nadu's rural heartland, is a film about Kaalaiyan, a highly respected and kind-hearted sarpanch of Soorakkottai, Thanjavur, and how he turns into a tiger-like protector when his sister's life is threatened by powerful enemies.
"Kaalaiyan" (Rajinikanth) is a very popular sarpanch in Soorakkottai, Thanjavur, for his truthful and just nature. He often has run-ins with "Nattadurai" (Prakash Raj), his sworn enemy who holds power through intimidation. In a courtroom case based on a conflict over property, attorney "Pattammal" (Nayanthara) comes into the picture and then develops a romantic relationship with Kaalaiyan after he helps her uncover the truth. But Kaalaiyan's emotional universe revolves around his younger sister, "Thanga Meenatchi" (Keerthy Suresh), whom he has raised as a daughter after their parents passed away.
Kaalaiyan tries his best to arrange a decent groom for Meenatchi, but his domineering nature becomes an impediment. The family also fixes a marriage with Nattadurai's brother without asking Meenatchi. When the wedding day arrives, she elopes with her lover, breaking Kaalaiyan's heart. Though embarrassed, he has the dignity to respect her decision and frees her to avoid bloodshed.
Meenatchi also moves to Kolkata along with her husband but has severe issues. Her husband is detained, and gangsters harass her. Kaalaiyan finds out about her issues and quietly steps in to protect her against Manoj Parekar, a powerful gangster. Following the death of Manoj, his revengeful brother Udhav begins to target Meenatchi. Kaalaiyan defends himself and eventually gets to meet his sister. She understands the sacrifices of her brother and asks for forgiveness.
"Annaatthe" intersperses family emotions, country background emotions, and action beats with Rajinikanth delivering power-packed performances. It hails brother-sister love and depicts the romance between a guard brother and free-spirited sister with high-stake emotions at junctures.