Karthiik's first lead role was in Peechankai (2017), a black comedy about an individual with alien hand syndrome, which he co-produced.

The film had earlier been made by the same team as a telefilm, with the director choosing to retain Karthiik in the lead role.

[1] The film won positive reviews from critics but had little impact at the Chennai box office.

[3][4] Karthiik next appeared in the political satire film, Yennanga Sir Unga Sattam (2021), where he portrayed two different roles.

[5][6] In 2022, Karthiik played the lead role in Dwarakh Raja's crime thriller Parole (2022).