Bommasandra Srinivasaiah Suryanarayana Murthy (16 March 1933 – 26 December 1985), known by his screen name Udaykumar, was an Indian actor and producer in Kannada cinema. He, along with Kalyan Kumar and Rajkumar, were called the Kumarathrayaru (meaning the three Kumars) of Kannada cinema He has authored many dramas and books. He has performed a broad range of roles and worked with all of the prominent actors of his day. He portrayed heroic characters early in his career later it became more nuanced villainous characters, often counterpointing Rajkumar’s heroic persona in historicals and mythologicals.