Irumbu Thirai (transl. Iron Curtain) is a 2018 Indian Tamil-language action techno thriller film directed by debutant P. S. Mithran. The film stars Vishal, Arjun, and Samantha Ruth Prabhu, with Yuvan Shankar Raja composing the soundtrack. The film was produced by Vishal Film Factory, and the venture began production in October 2016. The narrative centers around an army officer, who starts hunting down a gang of hackers after they steal money from his bank account.

The film released worldwide on 11 May 2018 and received positive reviews from critics and audience praising the cast performances(particularly Vishal and Arjun), writing, direction, action sequences and technical aspects. The film successfully completed 100-days at the box office and became the seventh-highest grossing Tamil film of 2018. Chakra, released in 2021, is unofficially considered to be a standalone sequel.