Favored Nations Films said members of Garland's family are expected to attend Thursday night's screening of the movie, which stars Waylon Payne and Ali Larter, at the Florida Theatre.
A question-and-answer session with Payne, the country music artist and actor who plays Garland, and the movie's director Rick Bieber is scheduled for after the screening.
"I think it was bold people that made this movie," Garland's brother Billy said in a statement. "It means everything to me that the truth of what happened to Hank is revealed after all this time."
Hank Garland lived the last four decades of his life near Jacksonville with Billy and his wife Amy, who cared for him after a near-fatal car accident and debilitating electroshock treatments ended his career.
He had recorded his hit album "Sugarfoot Rag" when he was 16 and played with artists like Hank Williams Sr., Elvis Presley, Roy Orbison, The Everly Brothers, Patsy Cline and Brenda Lee, his official Web site said.
He died in 2004 at the age of 74.
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