After joining a tennis camp at a local country club, twins Ashley and Bryce Timberline are blamed for outbreaks of vandalism there, and must work not only to clear their names, but also to find the real culprit.

The Timberline family makes a weekend getaway for a visit to a gold exhibit but it leads to a search for a stolen gold nugget and danger for the entire family.

Jake Konig, a famous horror novelist, disappears under mysterious circumstances, and the Timberlines become involved when the editor asks Bryce and Ashley's mother to finish writing Jake's last book.

When twins Ashley and Bryce Timberline investigate the burglary of a neighbor's house, they become involved with some alpacas and a guard dog as well.

Twins Ashley and Bryce get involved in another mystery when they observe strange goings-on near the alpaca farm, and, meantime, their school is imbroiled in a controversy over an annual day of public prayer.

At Halloween, facing a series of disasters while pet sitting, thirteen-year-old twins Ashley and Bryce gain insights into their principal and classmate Boo, and investigate a string of robberies at fast food restaurants in and around Red Rock.

While participating in a forensics contest, twins Ashley and Bryce investigate not only the disappearance of a college student but also behind-the-scenes dirty tricks during the public speaking competition.