When Walter the Cat, a local cat that has become famous for funny videos online, inherits a million dollars from his owner, the Aldens must find out who might be after the cat's money.

The Alden children visit a family friend at his apple orchard which is rumored to be haunted, but instead of a ghost they find that some of the families' valuable antiques are being stolen.

Bad luck strikes the Aldens when they help set up an exhibit at the Greenfield Museum. The main attraction is a 4,000-year-old mummy, and the longer the Aldens are around the mummy, the more things go wrong. The children soon wonder if it has brought with it an ancient curse.

Superstar watch : The Wundermutt dog food company is searching for a very special dog to be in their commercials, and the Aldens bring their dog. The spy in the bleachers : It's a big week at Cogwheel Stadium, the Clayton Cogs are playing for the pennant! The amazing mystery show: The Boxcar children have been chosen to be on an exciting new show! A camera crew is following the Aldens around the city of Philadelphia as they complete with another team...