"Twelve-year-old Milo is stuck spending the winter holidays in a house full of strange guests who are not what they seem-again! He will have to work with friends old and new to uncover clues in search of a mysterious map and a famous smuggler's lost haul"--

Eloise is a precocious six-year-old who lives at the Plaza Hotel and gets into all kinds of mischief.

"Leo has explored the zany, wonderful Whippet Hotel from basement to top floor, with trains, flying goats, and mazes (among other things) in between. But even Leo doesn't know every secret of the Whippet - and when he discovers that there's more beneath the hotel than he'd thought, it doesn't take long for more adventures to unfold!"--Dust jacket.

Someone is trying to put Aunt Jane's motel out of business, but the Alden children aren't going to let that happen.

"Two boys race to get an undercover alien back to her mothership while dodging an oddball group of UFO-chasers, TV newspeople, and Florida retirees"--

Ten-year-old Leo's future and the fate of the extraordinary Whippet Hotel, where his father is the maintenance man, are at stake when a series of cryptic boxes leads Leo to hidden floors, strange puzzles, and unexpected alliances.

At Greenglass House, a smuggler's inn, twelve-year-old Milo, the innkeepers' adopted son, plans to spend his winter holidays relaxing but soon guests are arriving with strange stories about the house sending Milo and Meddy, the cook's daughter, on an adventure.

Elizabeth, eleven, spends Christmas break at Winterhouse hotel under strange circumstances, where she discovers that she has magic, and her love of puzzles helps her solve a mystery.

Leo and Remi have gotten used to the strangeness of the Whippet Hotel, but when the entire top floor is hoisted into the sky and transported to the field of wacky inventions, they find that they must compete against a number of foes to solve a puzzle or lose their beloved hotel forever.

The peaceful winter that Mona the mouse expected at the Heartwood Hotel is disturbed by a difficult guest, food shortages caused by a huge blizzard, and secrets.