This transitional, hit-or-miss set, U2's first collaboration with producers Brian Eno and Daniel Lanois, followed 1983's breakthrough, War. When things click, it bridges that record's fight-the-power arena rock with the texture fetishism of its follow-up, The Joshua Tree. The transcendent "Bad" is the triumph, but the bonus disc adds fascinating experiments, including the excellent Bowie-drag outtake "Disappearing Act" and some funky B sides that borrow from Eno's Talking Heads playbook (see "Boomerang II"). They're working notes from the band's first great reinvention; it wouldn't be its last.