When the scholar Jeong Yak-jeon is exiled to Heuksando Island during the Catholic Persecution of 1801, he decides to write a fish-based encyclopaedia.
On the day that underground rapper Hak-soo fails his 7th audition, he receives a call from his hometown that his father is in the hospital. But he finds out that it was his father's plot to bring him to Byeon-san. To top it all, he is suspected as a phishing scam criminal and locked up in this small, boring suburb.
A mosquito from Transylvania finds its way to Seoul where it bites Na Do-yol, a corrupt police officer. Soon after he begins to develop a thirst for blood, and finds out that he has vampire super powers whenever he becomes sexually aroused. When Do-yol's past misdeeds come back to threaten his partner and girlfriend, he decides to clean up his act and sets out for revenge.
