Chun Sung-geun, who is proud of being a first-class healthy man with his sturdy muscles, is a physical educational teacher at Yeongmoon High School, which takes pride in its top educational enthusiasm in Korea. He always smells a bribe from parents using a vertically set 4th dimensional antenna. He often discovers students' fights and makes a bet of 100,000 won on them. As a persistent teacher, he has his students play soccer on sunny days and lets them have a self-study period on rainy days. One day he faces the greatest crisis ever in his 10-year life as a physical educational teacher. Yeongmoon High School has taken super strong measures by deciding to fire a physical educational teacher and replace him with an English teacher. Chun Sung-geun tops the list of teachers likely to be fired. There is a way out of every situation! He remembers the English teacher's certificate he obtained following a woman whom he loved unrequitedly. Now Chun Sung-geun must be an English teacher E.T., not an E.T. from outer space.