Professor Gangreen is a fictional character known for his role as a villain in various media, particularly in the animated series Captain Planet and the Planeteers. He is depicted as an evil scientist who seeks to exploit the environment for his own gain, often using toxic substances and pollution as his tools. His character serves as a representation of the dangers of environmental neglect and corporate greed. Through his schemes, Professor Gangreen highlights the importance of protecting nature and the consequences of ignoring ecological issues, making him a memorable antagonist in the fight for a healthier planet.