G.J. Echternkamp started filming Kansas band Split Lip Rayfield in 2005, intending to capture footage for a music video. What he ended up documenting, however, is the final days of the band’s charismatic and hella-passionate lead singer, Kirk Rundstrom. Rundstrom was diagnosed with cancer eight months into filming; after enduring intense treatment, he was nonetheless given two months to live. So what did this family man do? He went on tour. He and his three bandmates—one of whom describes their music as “all-acoustic, scorched-earth slamgrass”—play each show as if it were their last, since each easily could have been. The result is electric and touching and inspiring. Rundstrom is upbeat even when talking about his impending death, and is shown interacting with fans after shows though he’s wrecked. The highly entertaining doc focuses heavily on the music and rarely feels like a portrait of a dead man walking—even if, no spoiler alert, you know what somber closing note lies ahead.

Friday, June 24 at 8:15 p.m. at Discover HD Theater; also on Sunday, June 26 at 2 p.m. at AFI Silver 1.