On the closing Sunday of a four-night stand—July 13 through 16, 1967—the Charlatans headline the Avalon Ballroom, and there is a quiet symmetry in it that only hindsight makes visible. Two years earlier, in June 1965, these same men had detonated something in the desert: a six-week residency at the Red Dog Saloon in Virginia City, Nevada, that historians now treat as a genesis point for the entire San Francisco Sound. The handbill they made to advertise it—"The Seed," designed by George Hunter and Michael Ferguson—is widely called the first psychedelic concert poster. The Charlatans are routinely named the first of the underground San Francisco bands. And here, in mid-1967, at Chet Helms's Family Dog ballroom on Sutter Street, that lineage comes home.

It is the Summer of Love, though the phrase flattens what the room actually holds. The Charlatans arrive at the Avalon carrying a strange burden: they had invented the look and the myth of this scene and then watched their contemporaries—the Airplane, the Dead, Big Brother—sign to labels and eclipse them. They have no proper album. Their lineup is fracturing; Ferguson has been pushed out this very year, Dan Hicks is edging toward the front of the stage and, within months, out the door to form his Hot Licks. This is a band that helped write the scene's opening chapter, playing on as others turn the page.

The poster tells its own story. FD-71 is the work of Robert Fried, and it is his first rock poster—a commission handed to him by Rick Griffin to complete a triptych. Placed beside Griffin's FD-63 and FD-67, the three cards spell CHA / RLA / TANS, each bearing a Herb Greene photograph. Fried, Brooklyn-born, Cooper Union–trained, would make eighteen posters before turning to painting; he died in 1975. That this triptych, celebrating the band, features Ferguson—already gone—is the kind of small, human irony the era left lying around.

Beneath the Charlatans on the bill are two bands moving in the opposite direction. The Youngbloods, transplants gravitating toward the Bay Area counterculture, have just released "Get Together" as an RCA single. In July 1967 it is a commercial failure, stalling at number 62; its transformation into a generational anthem—gold-certified, Top 5—waits two more years, unimaginable from the vantage of this night. And the Other Half, a garage-psychedelic outfit formed in Los Angeles and resettled in San Francisco, bring the Yardbirds-and-Stones muscle of guitarist Randy Holden, who had been offered Jeff Beck's chair before choosing this harder, stranger path.

So the night braids three timelines: originators playing out their prime, a future anthem too early to be heard, a cult band cutting its brief run. No tape is known to preserve it. What survives is Fried's card and the fact of the date—a Sunday when the Avalon's first family took the stage they had, in a sense, made possible, while the scene they seeded rushed on without them.