Annaatthe (transl. Big brother) is an 2021 Indian Tamil-language action drama film directed by Siva and produced by Kalanithi Maran under Sun Pictures. The film stars Rajinikanth, Khushbu, Meena, Nayanthara and Keerthy Suresh while Jagapathi Babu, Prakash Raj and Soori appear in prominent roles. The music is composed by D. Imman while cinematography, editing and stunts are performed by Vetri, Ruben and Dilip Subbarayan respectively. It revolves around Kaalaiyan, a sarpanch in Thanjavur who goes to great lengths to protect his sister from the clutches of a businessman and his elder brother.

The film was officially announced in October 2019, marking Rajinikanth's first collaboration with Siva. Principal photography began on 11 December 2019, on the eve of the actor's birthday, and was completed within September 2021. The shooting process went on for one-and-a-half years, as a result of the COVID-19 lockdown in India and Rajinikanth's health issues in late-December 2020, delayed the film's production. The film was shot primarily in Ramoji Film City in Hyderabad, with few sequences shot at Chennai.

Annaatthe was released on 4 November 2021, coinciding with Diwali and received negative reviews from critics. Despite this, the film was a commercial success at the box office, grossing around ₹175–240 crore upon its release. It also crossed ₹150 crore in Tamil Nadu box office, thus becoming the third film to have this achievement. The Embassy of India announced the release of the film in Argentina as part of promoting culture and tourism.