When Johnny Cash walked onstage at Folsom Prison in January 1968, nobody applauded. All of the inmates in the crowded dining hall were told to stay silent until Cash spoke the infamous opening words of what would become one of the most successful live albums of all time: “Hello, I’m Johnny Cash.” Then the dining hall erupted.

Johnny Cash at Folsom Prison is a documentary that made its Canadian Premiere at the annual North by Northeast festival last weekend in Toronto. The film’s goal is to reveal the richer, untold stories surrounding Cash’s famed performance.

The film features interviews with Cash’s family, former band members, photographers, and ex-convicts who attended the event. Unfortunately, the film contains very little actual concert footage; it attempts to remedy this with a few superfluous animations accompanying the concert’s audio.

The most interesting feature of the film is the story of Glen Sherley, an ex-convict who turned into a professional singer/songwriter thanks to one song: “Greystone Chapel.” Sherley was an inmate at Folsom when Cash performed in 1968. Little did he know that Cash had heard a recording of “Greystone Chapel” the night before he was set to perform at Folsom. To Sherley’s surprise, Cash concluded his set playing his song. Cash and Sherley became close friends, and after his release Sherley became an inspiration for Cash’s campaign for prison reform.

By the end, the film is bittersweet. Any Cash fan will appreciate the interviews and stories, but anyone looking for stack of live footage will be disappointed. If you are not discouraged by that fact, then Johnny Cash at Folsom Prison is a revealing look into an album you only thought you knew. The film is availble as a bonus DVD in the At Folsom Prison Legacy Edition, along with two CDs of previously unreleased recordings from the performance.