The Penderwick family was being torn apart. The tearing wouldn’t last long—only two weeks—but still it was uncomfortable. Mr. Penderwick was the first to go, flying off to England with his new wife, Iantha, for scientific conferences and a bit of honeymoon. With them went Ben, Iantha’s son, who was too small to be without his mother, honeymoon or not.

That had been two days earlier, and now the remaining Penderwicks—four sisters named Rosalind, Skye, Jane, and Batty—were about to tear apart even more. Early the next morning, three of them would leave for Maine with their Aunt Claire, while the fourth headed to New Jersey with her best friend. The sisters had never been apart for an entire two weeks, and though all of them were nervous about it, the one going off on her own was the most nervous. This was the oldest, thirteen-year-old Rosalind, and she was having a terrible time accepting that her sisters could survive without her.

Right now she was waiting in her bedroom for them to arrive. She didn’t want to be in her bedroom—she wanted to be with five-year-old Batty, getting her ready for bed just like she always did. But tonight Skye and Jane, the two middle sisters, were helping Batty with her bath and pajamas. Practice, Aunt Claire called it, or a dry run. She’d thought it would calm Rosalind to see that indeed she wasn’t absolutely needed when it came to Batty. And Rosalind would have been calm, except that the others were supposed to come to her room as soon as they were finished, and that should have been at least ten minutes ago. How could a simple bath take so long? They knew she wanted to have one last MOPS—that is, Meeting of Penderwick Sisters—before Batty had to go to sleep. One last MOPS before they were all separated for two weeks.

“Two whole weeks,” groaned Rosalind, then looked up hopefully, because she heard footsteps in the hall. They were here.

But it was only one of them—twelve-year-old Skye, the second sister—and she didn’t have the look of someone who’d just conducted a successful bath. Her blond hair was hanging in damp clumps and there were wet spots on her tee shirt.

“It’s not as bad as it looks,” she said. “Batty’s fine. She didn’t drown or anything.”

“Then what happened?”

“Hound got into the tub with her.”

That explained why Skye was so wet. The Penderwicks’ dog was large and enthusiastic—getting him out of a bathtub would make anyone wet. But it didn’t explain why he’d been in the bathroom the first place.

“Hound always tries to get into the tub,” said Rosalind. “That’s why he’s not allowed near Batty at bath time. Didn’t you know that?”

“Nope, and neither did Jane. But we know it now, and we’ll clean up the bathroom later. I promise.”

A dry run! The irony wasn’t lost on Rosalind. She was determined not to scold, though, not this very last night. “Where are the others?”

“Jane is helping Batty with her pajamas. They’ll be here soon.” Skye shook her head violently, tossing droplets of water across the room. “Where’s your Latin dictionary? I need to look up revenge.”

“On my bookshelf, though I wish you wouldn’t.” Rosalind knew why Skye was thinking about revenge, and that she’d been thinking of little else for the last twenty-four hours. Which was absolutely not the best way to prepare for the next two weeks. With Rosalind off in New Jersey, Skye would be the OAP—Oldest Available Penderwick—and she needed to concentrate on taking care of her two younger sisters, not on carrying out revenge. “Daddy says the best revenge is to be better than your enemy.”

“I’m doing that, too. Almost anyone could,” said Skye, leafing through the dictionary. “Here it is. Revenge: ultio or vindicta. Then it says: to take revenge on is se vindicare in. Se vindicare in Jeffrey’s loathsome mother. How do I say Jeffrey’s loathsome mother in Latin?”

Skye’s desire for revenge was justified—Rosalind knew that. Jeffrey was Jeffrey Tifton, a boy the Penderwicks had met the previous summer while renting a cottage at his mother’s estate, called Arundel. By the time that vacation was over, Jeffrey was their excellent friend and honorary brother, and since then the sisters had seen him as often as they could, which was nowhere near often enough. He was always too far away—either at Arundel, a few hours west of the Penderwicks’ home in Cameron, Massachusetts, or at his Boston boarding school, a few hours east of Cameron. It had been natural then for the younger three sisters to want Jeffrey in Maine with them, and with great hope, they’d invited him.

After much dilly-dallying and back-and-forthing by his mother, permission had finally been given, spirits raised, ecstatic phone calls exchanged—until suddenly, just that morning, a mere twenty-four hours before departure for Maine, the permission had been withdrawn. Jeffrey’s mother had decided that he wasn’t going with the Penderwicks. He wasn’t going anywhere. He was stuck at Arundel for the whole summer.