There's no shortage of redundant documentaries about the life and artistry of John Lennon, but the 80-minute, unauthorized Inside John Lennon manages to cover the same old ground in a refreshing, thoroughly captivating way. The secret: a streamlined production making crisp use of file footage, film clips, and stills that haven't been over-exploited, an unsentimental tone, and an army of interviewees who knew Lennon in ways we don't often hear about. Among the latter are Tony Sheridan, for whom the early Beatles acted as a backup band; various members of Lennon's pre-Beatles group, the Quarrymen; Apple general manager Alistair Taylor; and Julia Baird, Lennon's sister. Choice audio quotes from Paul McCartney and George Martin are pure gold. Though the film covers familiar, major events in Lennon's life, the anecdotes and insights will strike most fans as new, while unguarded opinions of old confidantes are sometimes startling. --Tom Keogh