Green Knowe

Other supernatural entities in the series include the children's dog, Orlando; a demonic tree-spirit, Green Noah (manifesting as a large tree on the grounds of the manor house); and an animated statue of St. Christopher.

Toseland crosses floodwaters by night to reach the house, to spend the Christmas holidays with his great-grandmother, Linnet Oldknow, who addresses him as "Tolly".

Surrounded by the rivers and the floodwater, sealed within its ancient walls, Green Knowe is a sanctuary of peace and stability in a world of unnerving change.

Doctor Biggin has invited her niece Ida and two "displaced" refugee children, Oskar and Ping, to stay with her at Green Knowe.

The magic of Green Knowe is much more fantasy-based in this novel: the children see flying horses, meet a giant, and witness a Bronze Age moon ceremony.

During a visit to a zoo in London before his arrival at Green Knowe, he is fascinated by the giant gorilla Hanno; as a refugee, Ping feels a powerful bond.

The early chapters of the book detail Hanno's life as a young gorilla in Africa, and the trauma and cruelty of his capture, with great compassion and finesse.

This novel, the last in the sequence, tells the story of Roger d'Aulneaux, the son of the original Norman settler who built the manor house of Green Knowe.

Whilst exploring the overgrown countryside, Roger discovers two throne-like stones that allow him to access the turbulent time of the Conquest, then the later periods of Linnet, Susan, and Tolly, and them to visit him in turn.

"[11] In a study of "series fiction" at the turn of the century, Victor Watson opined that "A Stranger at Green Knowe is a masterpiece ... and in my opinion the greatest animal story in English children's literature".