In a reimagined Korean version of Sun Wukong, Son Oh-Gong (Lee Seung-gi) was punished and trapped for a thousand years. Ma-Wang (Cha Seung-won) tricked Seon-mi (Oh Yeon-seo) when she was a little girl into stealing from Son Oh-Gong a treasure he desired. Having released Son-Oh-Gong from his prison, he is contractually bound to Seon-mi to protect her whenever she called but he craftily ran away. 25 years later, they met again in a fateful encounter.