Consisting mostly of early-'70s material, this collection catches The Bee Gees in the midst of an evolutionary shift, not to mention a rare commercial dry spell. But by the very act of anthologizing one the trio's least-celebrated periods, it proves that the Gibb brothers' artistic growth continued even when they weren't under the world's microscope. The Bee Gees had left the baroque psych-pop touches of their '60s work behind, but they hadn't yet adopted the overt R&B influences that would lead to their world-beating disco sound of the mid-'70s. Barry, Robin, and Maurice's sui generis harmonies remained at the forefront, of course, and the group's way with a ballad became one of the most crucial items in their toolkit. Hits like "How Can You Mend a Broken Heart" (later covered by Al Green) and "Run to Me" overflow with romantic yearning and heart-stopping crooning—but so do the tunes that weren't even singles, let alone hits.