Adam Rex received a Bachelor of Fine Arts from the University of Arizona. Ironic Sans: Interview with Adam Rex, illustrator and author of "Frankenstein Makes a Sandwich" He has contributed illustrations to The Gathering and other fantasy art Adam Rex :: Pen & Paper RPG Database and has illustrated several children's books. Adam has noted that his history with fantasy drawings initially hurt his entry into children's books. Frankenstein Makes a Sandwich by Adam Rex - Interview - Harcourt His first books, Tree-Ring Circus and Frankenstein Makes a Sandwich, were published in 2006. Frankenstein Makes a Sandwich went on to become a New York Times best seller. Another picture book Pssst! and the illustrated novel The True Meaning of Smekday were published in 2007.
Adam received the Jack Gaughan Award for Best Emerging Artist in 2005.
His first foray into illustration of children's books, 2003's The Dirty Cowboy, written by Amy Timberlake, received positive reviews, including from The Capital Times, which described Rex's work as "gorgeous... This is his first book, but you wouldn't know it from looking. His artwork has real resonance". The Santa Fe New Mexican wrote, "The consummate skill of Rex's illustrations combines with wit and knowledge of the physical and emotional terrain". The book was banned at W.C. Andrews Elementary School in Texas in 2006. The book was removed from school shelves. The ACLU report noted that the "Principal did not want this book in the library." The book is the story about a cowboy taking a bath.
His illustrations of the book The Case of the Case of Mistaken Identity were reviewed favourably by The Gazette's critic, noting "a lively set of endpapers."