"Sagittarius" was a late-60s studio group devised by producer and songwriter Gary Usher. Usher had been involved with music as a songwriter since the early 60s (including writing lyrics for some of Brian Wilson's earliest songs), and soon branched out into production work. After considerable success as a producer, he eventually became a staff producer for Columbia Records. It was at this position that, during 1967, he found himself producing the pop group Chad & Jeremy. They had played him several songs, which he felt lacked any commercial potential. He had heard a demo around that time for a song called "My World Fell Down" (also recorded by British pop group The Ivy League), and he played it for them, thinking that it was a sure-fire hit. They balked at the idea of covering the song, and Usher felt that, if they weren't going to record it, he'd do it himself.
So, he brought in the top Los Angeles session musicians, as well as drafting friends such as Beach Boys touring alumni Glen Campbell (who did the lead vocal on the track) and Bruce Johnston for vocals. He finished off the recording by adding a musique concrete bridge. He presented it to Columbia executives under the gro...