The Little Hut
by Andre Roussin, Nancy Mitford

THE STORY: Three excessively sophisticated and elegant English people are shipwrecked on a desert island.

Philip and Susan are married, and Henry is the family friend, who, it turns out, has been something more than that to Susan for the past few years.

They never wanted to hurt Philip, and their chief concern has always been for his happiness.

But Henry, seeing Philip monopolize Susan on the island, isn't rather unhappy; he tells Philip about the old arrangement and after a great deal of discussion it's decided that Philip and Henry will share Susan on the island, as they did in the past.

This arrangement continues more or less happily, until an island native arrives and shows considerable interest in Susan.

From then on things become quite involved until a ship appears on the horizon to rescue them all.