Ellie Greenwich is far better known as a songwriter than a performer, having written (often in collaboration with Jeff Barry) numerous Brill Building and girl group classics in the 1960s, although she did have a hit as part of the Raindrops. She did, however, infrequently release some records under her own name. And of those, her 1965 single "You Don't Know" is unquestionably the best, even if it missed the charts altogether. As Alan Betrock wrote in his book Girl Groups: The Story of a Sound, "'You Don't Know' is the kind of record that not only transcends and expands the boundaries that come to mind when someone says, 'Girl-group record,' but it also can stand alone, totally unique and unmatched by any other competition." Though the record is lyrically a fairly standard lament of anguished love, it's produced with the drama befitting a mini-opera. Greenwich sings the opening lines with a measured drama against a spare, halting arrangement and arching soul-pop melody, the tempo somewhat reminiscent of those used on 1960s Drifters hits. But when it reaches the second part of the verse, a full band, strings, tympani, and backup vocals come in as the melody gets tenser, sadder, and more grandstanding, as if to mirror the narrator's increasing anxiety. Then it's back to the heartbeat-spare arrangement, and flip-flops between the hushed, subdued section and orchestral swells throughout the rest of the song. The instrumental break lets the strings and horns go to town a little more, dramatically dropping out to let a syncopated rhythm guitar and bass carry the melody. "You Don't Know" is a masterpiece of balanced tension, and was perhaps a little too unusual in its structure to become a hit single, even if tunewise it was up to snuff. Greenwich has said that the record stood a good chance of being a hit initially as it was slotted to be a "pick of the week" on New York station WMCA, but had its chances blown when Jackie DeShannon's "What the World Needs Now Is Love" became the pick of the week instead. That likely wasn't the only reason it didn't become a hit -- it customarily takes more than one radio station to break a record -- but it didn't help.