Mimi has taken her grandchildren Avery, Ella, and Evan on a surprise trip to the Grand Canal in Venice – only the surprise is on Mimi! Her special mystery writing suitcase containing her crucial-to-creativity mystery writing eyeglasses, monster coffee mug, and more has been stolen! Alas, so has a special historical mask that she has been lent to wear to the famous Black & White Ball. Who will save the day?

Avery, Ella, and Evan are used to bailing their grandmother out of mystery messes, but this time? They have their own problems! They get lost in the mysterious maze of side canals in the dark abroad a gondola. The only way they can solve the mystery seems to depend on the reader of the book. Unless you figure out the clues in the nick of time, the kids and Mimi will be up the canal without a paddle, Mimi’s writing tools, and the mask!