When Trixie Belden and Honey Wheeler find a cut diamond embedded in the dirt floor of the old abandoned gatehouse, they set out to find whoever left it there.

Not long after her family becomes wealthy, Diana Lynch's long-lost uncle appears and starts ruining her social life, causing Trixie Belden to investigate whether Uncle Monty is an imposter out to steal the Lynch fortune.

While organizing an ice carnival to raise funds for her pen pal's school library, Trixie investigates a mysterious problem facing Regan and a run of thefts and accidents in the neighborhood. There's a new kid in town-a tough boy from New York City who wears a black leather jacket and pointy cowboy boots. Trixie doesn't trust him for a second. She's sure about one thing: Don Mangan is trouble!

When his family moves into his recently deceased grandmother's house, ten-year-old Charlie meets a boy who also likes to skateboard, but then finds that his own special skateboard is missing.

While studying kung fu to try to overcome his clumsiness, Mark learns something that may interfere with his friends' plans for a group Halloween costume.

X's friends believe he can excel at any extreme sport, so when they want to check out the new climbing wall at the mall, he decides to hide his fear of heights rather than have them think him a coward.