The Aldens are excited to meet their favorite celebrity Walter the Cat, who makes the funniest videos on the Internet! And when this celebrity cat inherits a million dollars from his owner, he becomes even more famous! But someone seems to be angry about the will and is stealing things from Walter's house. Is this cat too famous for his own good?

When the Alden siblings visit their grandfather's friend in an apartment building, they begin to wonder about the many mysterious events that keep happening on the thirteenth floor of that building.

The Aldens are helping out at a doughnut shop, but when a rival store opens across town, strange events follow, and the children have a mouthwatering mystery to solve!

The Aldens are helping out at a rescue ranch for horses. Jessie's favorite is a beautiful horse named Dragon. When Dragon and other horses disappear from the pasture, the Boxcar children must saddle up for a mystery. What's happening to the horses at the Dare To Dream Ranch?

"The Boxcar Children are helping a friend find out more about their family's history. But what they find is a mystery going back generations! Can the Aldens help their friend unlock secrets of the past-- and present?" --

In this all-new very special miniseries, the Aldens have been recruited by a secret society to return lost artifacts and treasures to their rightful locations—all around the world! The Aldens follow a clue to Beijing, China, where they uncover their next mission—to return a mysterious clay artifact to its rightful owner. Their journey leads them to a scenic section of the Great Wall, but a thief threatens to ruin their trip and endanger their...

The Aldens are excited to learn about beekeeping. But when equipment goes missing, they have more than honey to harvest -- they have a mystery to solve!

In this all-new very special mini-series, the Aldens have been recruited by a secret society to return lost artifacts and treasures to their rightful locations—all around the world! After finding a painted turtle figurine, the Aldens are introduced to the Silverton family and Reddimus Society, a secret guild whose mission is to return lost artifacts and treasures to the sites they were taken from. The Aldens board a private train to New Mexico

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The Aldens, while testing the latest version of their favorite computer game, are surprised to find messages directed specifically at them.

Jessie wants her science fair project to make a difference. So when she gets the chance to test a local creek for pollution, she can't wait to get started. But when things start going wrong with her experiment, Jessie and her siblings don't just have an experiment to investigate, they have a mystery to solve!