The Guest List begins in the middle of the book’s narrative. On an island off the coast of West Ireland known as the Folly, Will Slater and Julia “Jules” Keegan have been married. The guests are celebrating on the night of the wedding as a storm nears the coast of the island. The island’s lights go out amidst the celebrations, and everyone hears a loud scream.

The beginning of the novel transports the reader back to the day before the wedding. Foley introduces the reader to Aoife and Freddy, the new owners of the island. Aoife is the wedding planner and her husband, Freddy, also assists her with the wedding preparations. They are both nervous for the guests to arrive; everything needs to be perfect if they want to begin attracting more visitors. Business has been difficult thus far, and they worry that nothing will change the fear the locals have of the island.

Later, as two guests, married couple Hannah and Charlie make their way to the island via boat, the