Dr. Nick Riviera is a fictional character from the animated television series The Simpsons. He is portrayed as a somewhat incompetent and unethical doctor, often seen wearing a white lab coat and a stethoscope. His character is known for his catchphrase, "Hi, everybody!" and his tendency to prioritize profit over patient care. In the show, Dr. Nick operates a medical practice that often features dubious treatments and questionable medical advice. He is frequently depicted as a caricature of a stereotypical quack doctor, providing comedic relief through his antics and misadventures in the field of medicine.