Titled "The Hook" after an onstage conducted signal frequently employed by FZ during this period, Volume 4 of Scott Parker's acclaimed Recordings Of Frank Zappa series dissects the recordings of Zappa during what fans refer to as "the Roxy era" from the fall of 1973 through the spring of 1974. The book includes a complete discography of the period as well as a thorough examination of the various "underground" or "bootleg" recordings made by audience members (and others) during this era. At 248 pages, The Hook is a fascinating trip into the heart of Zappa's Universe at a pivotal point in his career.