Echo (2015) by Pam Muñoz Ryan is a young-adult novel about the power of music to unite individuals across time, and even save lives: the wide-reaching novel follows an enchanted harmonica to 1933 in Germany, 1934 in Pennsylvania, and 1942 in California, before uniting the characters we meet along the way at Carnegie Hall in 1951. Covering the rise of Nazism in Germany, the tail end of the Great Depression in the United States, and the beginning of U.S. involvement in World War II and the internment of Japanese Americans, it examines the social issues of the period through the lives of young people. In each locale, the harmonica finds its way into the hands of a talented young musician who finds him or herself in need of courage and comfort in the face of personal upheaval that reflects the larger inequality and change in their social context. The harmonica passes hands between Friedrich Schmidt, Mike Flannery, and Ivy Maria Lopez, and eventually makes its way into the hands of Kenneth Yamamoto, a soldier whose life it saves during World War II.

The books begins with a prologue that introduces both a fairytale, and a scene of a young boy, Otto, reading that fairy tale as he hides in the forest, during a game of hide-and-seek. Lost in the forest, Otto is saved by the girls from that fairytale, Eins, Zwei, and Drei. They entrust him with an enchanted harmonica: if he passes it on, and it eventually saves someone’s life, they will be freed from captivity.

The first part of the book takes place in Trossingen, Germany, where Friedrich Schmidt struggles with his physical appearance during the rise of Nazism. An aspiring composer, he has a large, red birthmark on his face that causes him problems in a Germany where racial purity reigns supreme. He apprentices at a harmonica factory rather than attending school, and it is there that he discovers Otto’s harmonica, now painted with an “M.” As he plays it, he is emboldened. His family comes under scrutiny by the Nazi party when his father invites a Jewish musician over to play, and Friedrich hatches a plan to help his father escape Dachau, and to help both his Uncle Gunter and himself escape Germany. Before working his last day at the factory, he slips his harmonica into a box.

The second part of the book takes place in Pennsylvania. When their grandmother becomes sick, Mike Flannery and his brother, Frankie, go to live in an orphanage: the only one she can find with a piano for Mike to play. Their fortunes change when the wealthy heiress Eunice Sturbridge adopts them as a condition of her father’s will. As they acclimate to life in her mansion, her friend Mr. Howard buys Mike a harmonica, and a painted “M” confirms it is the one Friedrich gave up. Afraid that two boys are too much for Eunice, Mike hatches a plan to convince her to keep Frankie while he joins the famous Hoxie’s Harmonica Wizards. However, when he mistakenly believes that Eunice won’t adopt either boy, he tries to run away from New York and falls from a window while attempting his escape.

In the third part, Ivy Maria Lopez possesses the harmonica. She is a talented player and a young Mexican-American whose parents think music is silly. With her brother Fernando away at war, she is determined to be a “good soldier,” even when her parents move her away from her best friend to a new town, where she must attend a segregated school. There, a new friend convinces her that the Japanese family whose farm her family is tending might be spies. She puts her country ahead of her family’s prospect of long-term security, only to discover the Yamamotos were only hiding instruments for families placed in internment camps. She meets their son, Kenneth, and bonds with him, giving him the harmonica so that he may enjoy the comfort of music while at war.

In the final section of the book, we learn that all three characters have made their way to Carnegie Hall, where Friedrich will conduct the orchestra in which Mike and Ivy play. They have all had happy lives and successful careers as musicians. In addition, the harmonica saved Kenneth from a bullet, which, in turn releases Eins, Zwei, and Drei from captivity.