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!

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?