The book begins with Joey discussing with Rosalie Dene the possibility of having a reunion of 'foundation stones'. This comes about after Jo received a letter from Grizel Cochrane (living in New Zealand) saying that she will come to Freudesheim for a week or two. Grizel seems to be unhappy but cheers up after arriving at Freudesheim.
The reunion starts as a great success with people catching up with each other all over the place. The first excursion is with everyone to the Auberge where Bruno gives everyone a fright and then they split into parties. Con's group narrowly avoid a brush with death and Grizel then meets up with a former student who brings bad news but makes her feel better.
An amusing incident occurs and Margot's party have an adventure. This is followed by a foggy day although Joey, as usual, manages to find something fun for everyone to do. Unfortunately, the next day, Len's party have a misadventure, with Len herself being rescued by Grizel, who in turn gets quite seriously injured.
This turns out to be a blessing in disguise as Grizel was verging on a nervous breakdown, owing to the recent death of a friend's daughter and the subsequent marriage of a man she was fancying. Grizel is confined to the San but Joey manages to create a sensation during one of her frequent visits. Grizel begins to fall in love with one of the doctors and then leaves the San to live in Freudesheim, where she becomes engaged. The book ends with Grizel's realisation that things do get better.
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