What will the Aldens discover on a vacation to a beautiful island in the South Seas? The island is supposed to be deserted, but as the Aldens explore, they start to find signs that they suggest they are not alone.

The Aldens' dog, Watch, comes across a box with a note inside and soon the children are looking all over town for cleverly hidden boxes.

The Aldens investigate when the new coach of their community basketball league has her Most Valuable Player trophy stolen.

The adventures of the Alden family as they ride across country in a caboose that has a strange history--or is it a mystery?

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 untangle the mystery of the two houses. Relates the exploits of the four Alden children as they locate a missing man. The Boxcar children are determined to solve the mystery that surrounds an old yellow house on their grandfather's property. Strange things have happened...

The Alden children, isolated in a storm at a small bus station, are led into a mystery centering on a polluted river.

Someone is mixing up signs, switching off electrictity, and endangering the animals' lives at the zoo. If the Boxcar Children want to save the animals, they'll have to solve the mystery.

The Alden children help out a storeowner at the Hope Harbor Mall and discover that someone is tampering with the merchandise shipments.

The Aldens become involved in a community theater production of "The Wizard of Oz," which is systematically and mysteriously being sabotaged.

The Boxcar children have entered a detective contest sponsored by the local radio station, but some of the clues are phony.