The Aldens help restore an old library by cleaning up and clearing out old books. But while they work, they hear mysterious footsteps on the second floor. Then someone sneaks in and makes the library just as messy as before. Why would someone want the library to stay closed?

The Aldens take a paddle-wheel boat down the Mississippi River to visit their friend Cap Lambert in his cabin. But strange things are happening on Cap's property. When they see spooky flickering lights at night, the Boxcar Children must find out if the cabin is haunted!

Henry, Jessie, Violet, and Benny didn't think the old trunk in their house held anything interesting. But an unusual statue they find inside leads them to the Reddimus Society, a secret guild dedicated to returning lost treasures to where they belong.
Now the Aldens must help their new friends by traveling across the country with the statue and six mysterious boxes! Can the Boxcar Children keep these seven treasures out of the wrong hands?

The Aldens visit their cousins Joe and Alice, who live near an amusement park! The park has games, cotton candy, and a beautiful old carousel with wooden horses. But then Benny notices one horse isn't working and his favorite dapple gray has been damaged. Why would someone sabotage the carousel?