The Sinister Summer

Meet the Sinister-Winterbottoms: brave Theo, her timid twin, Alexander, and their older sister, Wil. They’re stuck for the summer with their Aunt Saffronia, who doesn’t know how often children need to eat and can’t use a smartphone, and whose feet never quite seem to touch the floor when she glides—er—walks. When Aunt Saffronia suggests a week pass to the Fathoms of Fun Waterpark, they hastily agree. But the park is even stranger than Aunt Saffronia. Something mysterious is happening at Fathoms of Fun, and it’s up to the twins to get to the bottom of it.

After leaving Fathoms of Fun, the kids are on their way to the next odd summer destination their aunt has chosen for them. This time, they find themselves dropped off at the Sanguine Spa in the “little Transylvania Mountains.” There they meet the owners: Mina, her mysterious little sister, Lucy (who is extremely pale, can’t go in the sunlight, and has an affinity for hanging upside down from the ceiling), and their intimidating guardian, the Count.

After leaving the Sanguine Spa in pursuit of Edgaren't, the kids find themselves at a mysterious summer camp, Camp Creek. There are lake games and happy counselors, and there's even a tie-dye cabin. It's all very . . . normal. But if Theo and Alexander know one thing, it's that normal doesn't always mean good. When everyone around her starts acting strange, Theo wonders if maybe the fumes from the tie-dye cabin are seeping into their brains, and she resolves to investigate what's really going on at Camp Creek.

After escaping from Edgaren’t and Dr. Jay, the Sinister-Winterbottoms and their friends arrive at Stein Manor Science Camp. They all work together to distract the friendly teenage camp director so they can explore and look for clues about where their parents might be. Meanwhile, Theo and Alexander settle on a daring plan. They know exactly where Edgaren’t is going to be: coming for them, and the books. This time, they’ll be ready.

Trapped in Aunt Saffronia’s spectral house, Theo and Alexander must work together to escape, stop their newfound nemesis Essa and her henchman Edgaren’t, save Wil and their friends, find their parents, and maybe, just maybe, get things back to normal. Following the clues left behind, the twins find themselves at Siren’s Song Seaside Amusement Park. Old faces and new surprises await them in a park that was built to lure in visitors…and their secrets.