Summer vacation on an almost private island gives the Aldens a challenge. Henry, Jessie, Violet and Benny used to live alone in a boxcar. Now they have a home with their grandfather and are spending the summer on their own private island. There is a mysterious stranger on the island with a secret--but that's not the only surprise in store for the Boxcar Children.

Relates the exploits of the four Alden children as they locate a missing man. The Boxcar children travel to Maine, take canoes into the wilderness and live in a house exactly like the one on Surprise Island, except the Maine house is brown, not yellow. They then untangle the mystery of the two houses.

Learning of the disappearance of Bill, a hired hand, the children meet a hermit who turns out to be Bill, and they reunite him with his wife.

Colorfully illustrated retelling of Aesop's fable in which the ants work hard all summer long to feed her children and store food for the winter, while their neighbor, a cheerful but lazy grasshopper, relaxes in the sun.

In this story about the Boxcar children, the Aldens find a castaway on a South Sea island, and must then find out how he got there and how they can help.