The Mystery of the Lost Avenger by Linda Maria Frank is a delightful adventure in the Annie Tillery Mystery series. A World War II wreckage unearths the discovery of love letters between a test pilot named Charlotte and her fiancé, which pulls Annie Tillery into uncovering her family history. Charlotte is Annie's great-grandmother and once Annie discovers the letters are coded, she can’t resist diving into the mystery of Charlotte’s life. With the help of her mother Carol and her boyfriend, they unravel a shocking secret that shines a light on the exciting life of her great-grandmother and allows her to learn about the women of World War II that worked on and test flew planes.

The mystery is centered on World War II and Annie’s family history. Linda Maria Frank brings to life an intriguing mystery that is lighthearted, emotional, and connects Annie with her family’s past. Annie’s relationships provide different elements to the story as she was primarily raised by her former NYPD detective aunt, who filled the void of mom and dad while also acting as the inspiration for her sleuthing. Her relationship with her parents is more background in her life with her father working out of the country and her mother a recovering addict. Woven throughout are flashbacks that unveil Charlotte’s experiences with the planes and show the events that led to the wreck and the coded letters. The letters are the biggest mystery to solve as Charlotte and her fiancé wrote to each other using code, which gives it a fun Nancy Drew flair. The story has a ghostly presence throughout that’s subtle and gives a physical connection directly to the past. The Mystery of the Lost Avenger is a charming mystery that is great for all ages and for those that love the classics of Nancy Drew and Trixie Belden.

Annie and her mother, Carol, are looking into a family mystery. Annie’s great-grandmother, Charlotte, was a WASP during the Second World War. Charlotte was also a bit of an amateur sleuth, just like her great-granddaughter, and it was her sleuthing into a potential saboteur that interwove into the present-day mystery when NCIS starts researching a recently discovered wreck from a plane that went missing in 1943. A mysterious note discovered in the wreckage is believed to have been written by Charlotte. With an old house and an attic full of trunks containing precious letters, diaries, photographs, newspaper clippings, and a secret code, there’s a lot of material to go through to solve the mystery behind the note and Charlotte herself. And, then there’s the ghost.

Linda Maria Frank’s young adult mystery novel, The Mystery of the Lost Avenger, is the fourth book in the Annie Tillery Mystery series. Full of clues and codes and ghosts, with a little touch of romance, the novel follows a compelling plot of sleuthing not unlike the popular Nancy Drew series. The story is told mostly through dialogue, which is well used to give the reader a sense of place, events and, of course, the characters themselves which are well developed. The mystery is well laid out to entice the reader to want to learn more not just about the mystery, but also about the WASP (Women Airforce Service Pilots) and other little-known details about World War II on the home front. The story is an exciting combination of mystery, history, romance, and a ghost.

The Mystery of the Lost Avenger by Linda Maria Frank is a YA mystery novel, perfect for tweens and teens that love history. Annie is about to leave for her first year of college when her mother discovers some clues about Annie’s great-grandmother, Charlotte. Charlotte was a WASP, one of the women that flew and delivered completed planes during WWII. Annie and her mother work together with Annie’s boyfriend, Ty, and others to put together the pieces of Charlotte’s history. They discover that Charlotte was trying to solve a mystery of her own, and Annie is inspired by her raw courage.

The Mystery of the Lost Avenger is the fourth book in a series, but you don’t need to have read the previous books to follow this one. The mystery is exciting without ever getting too scary or violent, and Annie and Ty have a sweet, clean romance going on the side. These elements would make me, as a parent, perfectly comfortable letting tweens/young teens read and enjoy Linda Maria Frank’s writing. I’ve always enjoyed historical fiction, especially about WWII. I loved reading about Annie and her mother going through old trunks together and finding little pieces of history. It reminded me of finding letters that my own grandparents had written to each other during the war. I also liked the complexity of Annie’s relationship with her mother and the way they moved slowly towards a healing place. It felt realistic. The Mystery of the Lost Avenger is a great book that can be enjoyed by many ages!