On Friday, August 12 and Saturday, August 13, 1966, Jefferson Airplane headlined the Fillmore Auditorium and the Grateful Dead opened for them.

That sentence is the whole story, and it is worth sitting with, because both halves of it sound wrong to a modern ear. The Dead were the second act — Bill Graham's poster puts the Airplane on top, and every archive that catalogs BG-23 lists them that way. And the Airplane on those nights were not the band anyone pictures. Their singer was Signe Toly Anderson.

Anderson had joined before the first album, sung on *Jefferson Airplane Takes Off*, and by that summer had a newborn daughter and was already weighing whether to stay. She lasted two more months. Her final show was October 15, 1966, in this same room; Grace Slick made her debut the following night, October 16th, on the same stage. So this poster documents the Airplane about eight weeks from the substitution that would define them — at the top of the bill, in the biggest room in town, in a version of themselves that most people have never heard.

The Dead were a five-piece: Jerry Garcia, Bob Weir, Phil Lesh, Bill Kreutzmann, and Pigpen on organ. No Mickey Hart — he was still more than a year from joining, though at least one major archive's records will tell you otherwise if you are not careful with them.

The poster is Wes Wilson's, and it carries a first: the photograph of the Dead on it is by Herb Greene, who by most accounts had not appeared on a Bill Graham poster before this one. Greene became the portraitist of the San Francisco scene, and his pictures of these particular musicians are now the images through which the era is mostly remembered. Wilson, who drew forty-five of Graham's first fifty posters and more or less invented the melting psychedelic lettering that says "San Francisco, 1966" to anyone who sees it, signed the printing into the blue background below the date. The Rock Poster Society notes it there: *Wes Wilson '66*.

And here is the honest part. Two of the most exhaustively documented bands in American music played two nights together in the most exhaustively documented room in San Francisco, and no setlist survives for either night. No tape circulates. Nobody wrote down what they played. The poster is what is left.