Books in Fourth-Floor Twins series

Two sets of twins launch a wild chase when the "disappearing parrot" in their school talent show magic act really does disappear.

In an extraordinary day at the beach, after winning a sand castle contest, two sets of twins resolve the mystery of the disappearance of a rich woman's dog.

When a famous sculpture is stolen from the museum, two sets of twins team up to track down the thief.

When a famous sculpture is stolen from the museum, two sets of twins team up to track down the thief.

Two sets of twins catch a thief while tracking down a missing suitcase in a train station.

Two sets of twins receive a message in a fortune cookie, warning them to beware of a man in a blue hat.

In an extraordinary day at the beach, after winning a sand castle contest, two sets of twins resolve the mystery of the disappearance of a rich woman's dog

Twin sisters Donna and Diane join their fourth-floor neighbors, Gary and Kevin, in tip-toeing past some red herrings to discover the identity of a fish thief

Two sets of twins catch a thief while tracking down a missing suitcase in a train station.

An unusual mystery involving fortune cookies and their contents requires identical twins Donna and Diane and their neighbors, Gary and Kevin, to deal with some half-baked theories

Two sets of twins suspect their neighbors of wrong-doing when they observe the strange behavior of the couple's nephew.

Identical twins Donna and Diane help their fourth-floor neighbors, twins Gary and Kevin, make a talking parrot disappear during a magic trick at the school talent show, but problems occur when the bird really vanishes