Imagine Dragons begins this exclusive live session with an acoustic recasting of the two singles that put them on the map, “It’s Time” and “Radioactive.” And while these alone make a satisfying offering for fans of the band’s multi-platinum debut, Night Visions, the most exciting material comes at the end, when the Las Vegas group delivers a pair of yet-unreleased tracks: a delicate, harmony-rich ballad, “30 Lives,” and a spirited, uptempo sing-along, “Destination.” Regardless of whether the songs are familiar or new, the stripped-down accompaniment of acoustic guitar, mandolin, and strings has the casual feel of a living room jam session, allowing an intimate perspective into Imagine Dragons’ songwriting.