In 1887, the social-climbing Cranstons voyage from New York to London, where they hope to find a husband for their awkward older daughter, secretly accompanied by Helena and her mouse siblings, for whom the journey is both terrifying and wondrous as they meet an array of titled humans despite their best efforts at remaining hidden.

Fifth-grader Alex Trumble builds a "dingus"--a time machine--when his brother Stephen is kidnapped by dangerous, evil time-travelers, to get back to the past and into the future to save his family from disaster.

Happy to be adopted at last, twelve-year-old orphan Mary Hayes soon learns a terrifying secret about her new mother, the mysterious Madame Z.

Beastologist-in-training Nathaniel Fludd and his Aunt Phil nurse a mysteriously ill unicorn, try to stop Obediah from taking the unicorn's horn, and finally get a solid lead on the whereabouts of Nathaniel's parents.

In 1928, when timid ten-year-old Nate learns that his parents have been lost at sea, he joins his father's cousin on a flight to Arabia where they must oversee the death and rebirth of the phoenix, thus beginning his training as a "beastologist."

The continuing adventures of beastologist-in-training, Nathaniel Fludd, as he accompanies his intrepid Aunt Phil on a dangerous mission across West Africa to find a deadly basilisk that is missing and begins to find clues relating to the mysterious disappearance of his parents.