Thin Lizzy's story starts, oddly, at the end: a remix session for the Jailbreak album with guitarist Scott Gorham and drummer Brian Downey, before the film loops back to the beginning. Archive footage traces singer Phil Lynott through his pre-Lizzy Dublin bands, the Black Eagles and Orphanage, and follows him, Downey and guitarist Eric Bell forming the three-piece that took its name from a robot character in the Beano comic. Interviews with Bell, Downey, the band's first manager, and the executive who signed them cover the lean early years before Brian Robertson and Scott Gorham joined to form the twin-guitar lineup that made the band's reputation. Rare stills, some never broadcast before, sit alongside contemporary TV performance clips and a mix of hits and lesser-known tracks. The film does not smooth over the harder parts of the band's history, built instead from the people who were actually there in the rehearsal rooms and tour vans.