Delightfully creepy but not too scary at any given time, which is a great balance to strike. Cautious, law-abiding Kendra and her impulsive brother Seth are dropped off at their grandparents’ for the summer; their grandfather Stan seems less than happy with this arrangement, and the children soon find out why, setting themselves up for a summer of magic, adventure, and plenty of opportunities for desperate bravery. I liked how both child and adult characters were given space to both make mistakes and learn from them, in a way that felt organic to the story and not forced. No particularly new ideas here, but very smoothly executed. Ties up the biggest conflicts at the end, but leaves lots of nice open ends for sequels.