"Baek Min-hyeok is a veterinarian who doesn't particularly like or dislike animals. One day, while on his way to meet his old schoolmates, he encounters a scumbag on the Mapo Bridge trying to throw a Sapsali puppy into the river.

Was it professional instinct? He threw himself into the Han River to save the puppy. Just as he thought he was facing his death...

— 'Huh? He’s awake! Are you okay? I was so worried because you were unconscious!'

— 'I hate surgery! Doc! I really don't want to lose my "peanuts" (neutering). Please!'

He starts hearing the voices of animals—voices he shouldn't be able to hear.

This is the story of veterinarian Baek Min-hyeok and his new 'cheat key': the ability to converse with animals."