Sethu made his acting debut in the 2010 Tamil drama film Mynaa, directed by Prabhu Solomon, in which he had played one of the lead characters. Although he had offers post Mynaa, he did not accept any role as he did not want to sideline business, since it was the period of Great Recession. Three years later, he acted in his next film, Thank You directed by V. K. Prakash, which marked his Malayalam debut. In 2014 he acted in the Telugu release, the romance Manasunu Maaya Seyake that featured him in the lead role, after which he appeared in the Malayalam thriller 100 Degree Celsius directed by Rakesh Gopan.