Teacher (Noda Tetsuya) is a former doctor with a mysterious artificial hand. On the other hand, Dr. Chocolate (Tershima Yui) is a 10-year-old with prodigious surgical skills and can perform any kind of operations. Joined by six other medical friends, they are known as the "Chocolate Company" and perform top-secret operations with a mysterious condition of 100 million yen in cash and chocolates.