I feel like it’s not summer if Beatriz Williams doesn’t have a book out. A Certain Age is her latest. It’s a 1920s retelling of the opera Der Rosenkavalier. Every other chapter tells either Theresa or Sophie’s story. These stories intertwine as the book progresses. Theresa is unhappily married and having an affair with Octavian as the story begins. Sophie then gets engaged to Theresa’s brother, Ox. Sophie, at the same time, falls in love with Octavian. A mystery is woven through the tale to add to the intrigue. A Certain Age is another hit for Williams and one I very much enjoyed reading.