Neyla Pekarek has been the cellist for Denver folk-rock group The Lumineers since 2010. Despite that band's demanding touring schedule, the Colorado native found time to write and record the original folk opera "Rattlesnake," which she'll release as an album later this year. It's based on the life of Northern Colorado pioneer "Rattlesnake" Kate McHale, who in 1925 allegedly killed 140 snakes to save her life and that of her three-year-old son. Pekarek and her band visited the CPR Performance Studio to play four songs from "Rattlesnake." She also spoke with Alisha Sweeney about how she discovered the story of Rattlesnake Kate as a student at the University of Northern Colorado, recording the album with M. Ward in Portland, Ore., and going on tour with U2 last year.