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

On a camping trip to Arizona with their grandfather, the Alden children search for a lost gold mine.

When they help out at a guide dog training school, the Alden children meet several people who seem obsessed with a particular dog named Ginger.

At the same time that the Alden children's efforts to raise money for a new hospital wing are being sabotaged by nasty tricks, they find their attempts to befriend the new girl, Beth, frustrated by her strange behavior.

In the months after her sister dies, seventeen-year-old Lennie falls into a love triangle and discovers the strength to follow her dream of becoming a musician.

The Aldens investigate when an old wooden mask they have found is stolen.

When Lizzie and Gael share an irresistible challenge, to find the peacock ring that once belonged to artist Frida Kahlo, Paloma decides it is the perfect way to honor her father.

The ordinary interactions and everyday routines of the Watsons, an African American family living in Flint, Michigan, are drastically changed after they go to visit Grandma in Alabama in the summer of 1963.

While staying at a hotel in New York City, the Aldens investigate a series of annoying pranks plaguing the management and guests.

The Alden children plan to ride in their boxcar at the Greenfield Founders' Day Parade, but the newly refurbished boxcar is stolen a couple of days before the big event ... with their dog, Watch, in it.