The 33-year-old actor will also be lending his vocals for the film, as he will sing from the entire Williams catalog, including hits like 'I'm So Lonesome I Could Cry', reported E! Online.
The movie will chronicle Williams' triumphant rise to fame and its ultimately tragic effect on his personal life and his health (Williams died at the young age of 29 due to heart failure).
'I Saw the Light' will be directed by Marc Abraham from his screenplay based on Colin Escott's award-winning biography and produced by Aaron L Gilbert alongside Brett Ratner, G Marq Roswell and Abraham.