Randolph Caldecott (1846–1886) was one of the first artists to illustrate children’s books with an eye toward merriment rather than morality, so it’s not surprising that this action-oriented biography by Markel (Out of This World) offers “a hero so chipper he can barely hold still on the paper.” Working in watercolor and pen and ink, McClintock (Vroom!) first shows Caldecott as a bearded young man pulling back an outsize book page to reveal a throng of his drawings come to life. As a boy, Caldecott sketches the animals he loves in motion; as a young man, he confounds his father’s efforts to make him a banker, draws during work hours, and works to improve his skill. Soon, he’s an artist with an offer to illustrate books for children, and “he likes what kids like—action!” Here, reproductions of Caldecott’s own real-life images enter the book as he enjoys his first publishing success. The historical moment of this innovation is captured with verve and verb-forward flourishes in this lively portrait of a person whose illustration style still inspires contemporary picture book creators, some of whose portraits are slipped into a final scene. Characters are presented with various skin tones. Ages 5–8.