The Aldens try to help a visiting Russian gymnast who is surrounded by mysterious people and events and who seems to have a secret.

When twelve-year-old Gregor finally learns the ancient prophecy, which foretells his death, he must gather his courage to defend Regalia from the army of rats, take his mother and sister home safely, and fight his own dark side.

The Aldens participate in a three-day bicycle ride and soon find that someone seems to be intent on keeping others from completing the event.

The Alden children investigate the old boxcar where they used to live to find out if something that happened long ago is now haunting it.

Two sisters. One chance for the throne. Drizella and Anastasia know only one thing for certain: they will never end up like their mother, Lady Tremaine. The only version of Lady Tremaine that they know is a bitter and cruel head of house. They have promised themselves they'll find love, see the world, and never let their hearts turn so cold. But fueled by Lady Tremaine's tendencies to pit her daughters against each other, Drizella and Anastasia find...

The Alden children search for buried treasure on Blizzard Mountain, but a mysterious rival treasure hunter is determined to chase them off the mountain.

The Aldens investigate when the arrival of several suspicious characters in Greenfield coincides with a mystery involving a popular boy actor.

Can the Boxcar Children find a treasure in a neighbor's attic before a rival finds it first?

The Aldens investigate when a new store called the Game Spot opens in town and the neighboring shops are robbed.

When their grandfather arranges for them to spend two week at Sunny Oaks, the four Alden children enjoy settling into the routines of farm life but become suspicious about a mysterious horse locked in the stables.