In this second book of The Horrible House series, Holly Spinatsch wakes up from what she believes was a dream until a slew of clues leads her to conclude that what she experienced at The Children's Horrible House may have indeed occurred. Her sister's dog runs away and with him her hopes of seeing her "horrible" friends becomes bleak. After being enrolled in a new school, her hope is revived when she sees Coriander, her closest ally she met during her stay at the mysterious mansion. With him, she decides to go back but they are not sure how to get there until a note from Holly's older sister Juniper jumpstarts their resolve to return. Meanwhile Sirius Pankins, the director, is plotting a trap to force these kids to find what she believes is a rightful fortune but nostalgic flashes from her lost family cause her to lose sight of her goal.