Soon, however, surprising things start to happen, including the unexpected arrival of Zachary Gray, a charming but troubled college student whom Polly met in Greece and dated in Cyprus the year before (in A House Like a Lotus).

Then, while walking near her grandparents' Connecticut home, Polly meets druids Karralys and Anaral and a warrior named Tav, all of whom lived in the area some three thousand years ago.

The Murrys and the Colubras try to protect Polly from being drawn into the past, but although she tries to obey their restrictions on her movements, she continues to encounter Anaral and the others.

On Samhain, Polly feels a compulsion to visit the Murrys' indoor swimming pool, the modern location of a site considered sacred by Karralys, Anaral, and their tribe.

His heart, previously seen as damaged by rheumatic fever in the Austin family novel The Moon by Night, is now so weak that he does not expect to live much longer.

Tynak, the current leader of the People Across the Lake, promises to let the tribe's medicine man heal Zachary's heart if he helps bring Polly to them.

Ultimately, Polly's spirit of self-sacrifice and love, accompanied by the timely return of rain on her captors' side of the lake, wins out as a better way to interact with the Divine than an offering of death.

The other volume in the Time Quintet, Many Waters, is about Polly's twin uncles on her mother's side, Sandy and Dennys Murry.

In An Acceptable Time, Zachary makes specific reference to his desertion of Vicky Austin at the end of A Ring of Endless Light.

Last but not least, Polly's experience with the People of the Wind is consistent with Charles Wallace's interactions with the same tribe in A Swiftly Tilting Planet.

[1] As for Polly's own past adventures, she refers repeatedly to Gaea, her home in The Arm of the Starfish, and mentions the Quiztano people from Dragons in the Waters.