Thirteen-year-old fraternal twins Dallas and Florida have grown up in a terrible orphanage but their lives change forever when an eccentric but sweet older couple invites them each on an adventure, beginning in an almost magical place called Ruby Holler.

Avoiding relationships to protect her sensitive heart, plus-sized Molly supports her once-cynical twin, Cassie, when the latter has her own bout of lovesickness, a situation that is complicated by sibling dynamics and an unexpected romantic triangle.

On a cross-country vacation with their parents, twins Coke and Pepsi, soon to be thirteen, fend off strange assassins as they try to come to terms with their being part of a top-secret government organization known as The Genius Files.

When professional typist Letitia Glover is desperate to learn more about the fate of her twin sister Flossie, Enola enlists the help of her brother Sherlock and her friend Tewky to investigate Flossie's husband, the sudden death of his first wife, and the mysterious appearance of a black barouche.

Assuming her twin's identity, Frey works to destroy her father. When a rebel uprising strands her in Pas, and the city comes under attack, Frey must step out of the shadows to find her missing sister and take action against her tyrant father.

Eleven-year-old twins Miles and Beckett Fowl enjoy adventure and mayhem while helping a troll escape nefarious forces that want his magic.-- One week after their eleventh birthday, the Fowl twins-- scientist Myles, and Beckett, the force of nature-- befriend a troll who has clawed his way through the earth's crust to the surface. Unfortunately the troll is being chased by a nefarious nobleman and an interrogating nun, who both need the magical creature...

While Connor and the Pirate Federation attempt to stop a new ship of vampirates, his twin sister Grace and their long-lost mother Sally reunite, and Sally reveals some news that is devastating for the twins.

When the Pirate Federation and Nocturnals form an alliance to battle the renegade Vampirates, twins Connor and Grace Tempest each have important roles to play in the war--he as a pirate warrior and she as a powerful healer working with the war-wounded.

"Following clues left by their missing father, twelve-year-old twins Bickford and Rebecca Kidd sail from the Caribbean to New York City with their siblings to finish the dangerous quest of their world-famous treasure-hunting parents"--Provided by publisher.

Connor's time aboard the pirate ship "Diablo" has him longing to be a part of the pirate life, while his twin sister Grace prefers he choose the less dangerous path of attending the distinguished Pirate Academy.