Set during WWI, ‘Mary Louise and the Liberty Girls’ is the fourth book in the popular children’s series by ‘Oz’ author L. Frank Baum. Mary Louise and her friends decide to form a group to help raise money for the war effort, calling themselves the Liberty Girls. When the group hears about anti-war sentiment being spread in the town, they task themselves with discovering whether it comes from a spy hidden in their midst. Lyman Frank Baum (1856 – 1919) was a prolific and well-known American writer. He is best known for his famous series of modern fairy tales set in the imaginary land of Oz. The first of the books, ‘The Wonderful Wizard of Oz’ is widely considered to be the first true American fairy tale and was the basis for the hugely popular 1939 classic musical ‘The Wizard of Oz’ starring Judy Garland. Born and raised in New York, Baum held a range of jobs including as a poultry farmer, clerk, and storekeeper before pursuing his talent for writing at the age of 41. He wrote 14 novels in the Oz series, as well as over 40 other novels and over 80 short stories. He died in California in 1919.