Doctor Yellow is a fictional character from Shinkansen Henkei Robo Shinkalion, based on the real-life Doctor Yellow inspection train. In the series, the character is associated with the Shinkalion project and serves as a distinctive, mysterious presence connected to railway safety and advanced train technology. Doctor Yellow’s role emphasizes observation, testing, and support rather than frontline combat, making the character important for uncovering problems and ensuring the system functions properly.