Robert C. O'Brien (1918-1973) was born in Brooklyn, New York. He attended Williams College and graduated from the University of Rochester. He was a writer and editor for Newsweek, National Geographic, and other publications. He lived in New York City and then in Washington, DC, with his wife and four children. Z for Zachariah-which is now a major motion picture starring Margot Robbie, Chris Pine, and Chiwetel Ejiofor-was completed by his wife and daughter, with the help of his notes, after his death. He is also the author of Mrs. Frisby and the Rats of NIMH and The Silver Crown.

Zena Bernstein has a BFA from Syracuse University. She began her career as a book illustrator in New York City. Zena uses a combination of watercolor and acrylics in her work. Through a meticulous process, she carefully places several layers of dots of pure color to suggest subtle tones and shades. She refers to her creative work as a labor of love. Her drawings range from the natural world of mushrooms and insects to the unseen world of fairies and gnomes. She's perhaps best known for illustrating the children's book Mrs. Frisby and the Rats of NIMH. Zena currently calls Canada home; it's also the home of the fairies she draws and writes about.