Reader recommendation: The Invisible Ones Monitor readers share their favorite book picks. By Jeanne Heller, Los Angeles April 19, 2012 About video ads View Caption of Stef Penney’s The Invisible Ones is a fine mystery with a twist at the end and a touch of romance. It takes place in modern times among the Romany (Gypsies) in southeast England. I now want to read Penney’s earlier novel, “The Tenderness of Wolves.” Can you guess which literary work goes with each final line? Take our quiz!