Watch Online Free on Watchseries. Grahan is an Assamese language romantic drama film directed by Tilak Sarma and produced by M.Choudhury under the banner of BMC Media Production, Guwahati. It stars Diganta Hazarika, Farhin Choudhury in the lead roles.The story, written by Bilkis Mazumdar, is based on love and friendship as seen through the eyes of the younger generation.