A lonely widow lives in a big, old house atop a hill outside of town, a house suspected as haunted. Certainly, the aging matriarch is haunted, and not only by longing for her departed loved ones and for her estranged, grown children. Her house seems to develop an unknown agenda of its own, with a persnickety furnace and lights that turn on of their own volition. Most frightening of all, though, are they knocks that resound at the strangest times, causing the widow to retreat. The family calls in a team of paranormal investigators to get to the bottom of the paranormal happenings.

At its heart, “Knock Knock” by Heather Miller is an exploration of family love. Though estranged from her own children, the protagonist, Millie, exudes care for her grown son and daughter. Family can be difficult, indeed. The book has an interesting premise, reads easily (though my print version’s small font gave my myopic eyes trouble), and provokes thought. Fans of classic ghost stories such as “The Haunting of Hill House” or “The Others” will enjoy this book.