The Avalon opened its own weekend on September 9, 1966, on Mouse and Kelley's FD-25, with Quicksilver Messenger Service over the Great Society.

The Great Society is the reason to look closely at this bill. This was Grace Slick's band — her brother-in-law Jerry Slick on drums, his brother Darby on guitar — and in September 1966 she was still in it. Within about five weeks she would leave for Jefferson Airplane, and the Great Society would dissolve almost immediately after. The band that had been advertised on BG-25 three weekends earlier, bumped from a Fillmore bill by Sopwith Camel while Slick's photographed face sat at the centre of that very poster, had roughly a month left as a going concern.

Quicksilver, headlining, were still a year and a half from their first album.