Robert Louis Stevenson significantly contributed to a shift in literature by moving away from the rigid structures of Victorian literature. His works, such as "Strange Case of Dr Jekyll and Mr Hyde" and "Treasure Island," introduced elements of psychological exploration and adventure that emphasized the complexities of human nature. Moreover, Stevenson's blending of genres and his focus on moral ambiguity paved the way for modern narrative techniques that challenged traditional storytelling, marking a transition toward more ambiguous and multifaceted literary forms. His influence can be seen in later writers who embraced similar themes and styles.