Ayalaan ( transl. Alien) is a 2024 Indian Tamil-language science fiction action film directed by R. Ravikumar and produced by KJR Studios. The film stars Sivakarthikeyan and Rakul Preet Singh in the lead roles, alongside Sharad Kelkar, Isha Koppikar, Karunakaran, Yogi Babu, David Broughton-Davies, Bhanupriya and Bala Saravanan, with Siddharth voicing the titular role. It follows Thamizh who teams up with Tattoo, an alien, to stop Aryan, a rogue scientist, from making a deadly Nova gas, which would endanger the Earth.

The film was announced by 24AM Studios in October 2016, but the studio backed out before KJR Studios took over, and principal photography commenced in June 2018. The film was predominantly shot in Chennai, and wrapped by early-January 2021 after delays due to financial issues, Sivakarthikeyan's other commitments and the COVID-19 pandemic, while additional photography took place in November 2022. The film has music composed by A. R. Rahman, cinematography by Nirav Shah and editing by Ruben. It has over 4500 visual effects shots, the most for an Indian film.

Ayalaan was released theatrically on 12 January 2024, during the week of Pongal, after having been delayed from Diwali (late 2023) due to unfinished post-production works, and received positive reviews from critics. A sequel was announced shortly after its release.