A house on the edge of the world UA - Dean Koontz

Katie, 36, lives alone on the small island of Jacob's Ladder in a stone house that looks more like a fortress, far from civilization. Once a star of the art world, she is now escaping from a terrible loss in solitude and painting. There is not a soul around, no internet or television, only a few CDs of classical music. Katie doesn't communicate with the inhabitants of other islands, only occasionally visits the mainland - she doesn't want to reopen the wounds she has been healing for so long. Her reclusive life is disrupted by agents of a secret government research center located on the neighboring island of Ringrock. They refuse to explain what or whom they are looking for. Despite their menacing appearance, Kathy realizes that an even greater threat is looming over the world. Soon, she finds herself in the midst of a terrifying battle with a mysterious enemy.