A well-known genre and portrait painter, he created paintings that appealed to post-Civil War genteel Victorian tastes. He was born and raised in England where he received his formal art training before immigrating to New York City in 1854. He worked in the Tenth Street Studio Building and was a studio neighbor of John George Brown who influenced his work. Many of Guy's scenes were children in interiors and were expressions of his interest in the education of children. His paintings have smooth, lacquered finishes because of the glazing processes that he learned in England. He was also skillful with hidden light sources on his figures.