Warner, Gertrude Chandler

On a camping trip to Arizona with their grandfather, the Alden children search for a lost gold mine.

During a trip to Oregon, the Aldens are astonished when Watch discovers a backpack filled with valuables, a finding that compels them to learn what happened and return the backpack to its rightful owner.

While helping run Jerry Taylor's general store, the Alden children investigate his mysterious employee Nancy.

While spending two days touring a zoo to see the baby animals, the four Alden children, aged six to fourteen, help catch an escaped monkey, participate in a photography contest, and investigate a missing camera.

Grandfather Alden and the four children rent an old lighthouse for a seaside vacation, but find their peace disturbed by strange nocturnal noises.

The Aldens stay in an old castle in Ireland and wonder if the mysterious figure they see on the grounds at night could be a banshee of ancient legend.

When the Aldens help out at a harvest festival in the Rocky Mountains, they investigate local rumors about a werewolf terrorizing the town.

The Boxcar Children volunteer to help clean up the old abandoned school in Silver City, even if some are scared by all the spooky goings-on.

While visiting a recent purchase of Grandfather's, a ghost town in the Rocky Mountains, the Aldens encounter a mystery involving a run-down motel and a woman who may be a ghost.

While vacationing at a friend's country home, the four Alden siblings try to find a long-missing, priceless brooch and investigate the existence of a ghostly stream.