Elizabeth Olsen has joined “The Avengers” star Tom Hiddleston in the Hank Williams biopic “I Saw the Light,” and will play his wife, Audrey Mae.

Brett Ratner’s RatPac Entertainment, Bron Studios and Creative Wealth Media Finance are producing and financing. Production is scheduled to begin in October in Louisiana.

Veteran producer Marc Abraham will direct from his own script, which is based on the 1994 book “Hank Williams: The Biography” by Colin Escott, George Merritt and William MacEwen.

Aaron L. Gilbert will produce with Ratner, Abraham and G. Marq Roswell. James Packer, Ratner’s partner in RatPac, will exec produce.

Producers have obtained rights from Sony ATV for Williams’ songs, including “Your Cheatin’ Heart,” “I”m So Lonesome I Could Cry” and “Hey Good Lookin’.”

Williams was born in 1923 in Alabama and broke out in the post-World War II era with the song “Move It on Over.” Among his hits are “Lost Highway,” “Jambalaya (on the Bayou),” “Ramblin’ Man,” “You Win Again” and “Lovesick Blues.”

He suffered from spina bifida and died at age 29 of heart failure after struggling with alcoholism and addiction to prescription pills.

Olsen recently completed “The Avengers: Age of Ultron” and was seen this summer in “Godzilla.” She is repped by Gersh and Brillstein Entertainment.