First published in 1899, it tells the story of Dora, Oswald, Dicky, Alice, Noel, and Horace Octavius (H. O.) Bastable, and their attempts to assist their widowed father and recover the fortunes of their family.

"This is the story of the different ways we looked for treasure, and I think when you have read it you will see that we were not lazy about the looking."

This novel, the first in what is often called "The Bastable Saga" begins the story of these six children -- Dora, Oswald, Dicky, Alice, Noel, and Horace Octavius Bastable. When their mother dies and their father's business fails, the children embark on a series of adventures. Its sequels are The Wouldbegoods (1899) and The New Treasure Seekers (1904).