Being able to see ghosts and other supernatural spirits is a heavy responsibility. Prince Lee Rin (Jung Il-woo), like his father before him, discovers that he has the ability to see ghosts and other supernatural beings. Armed with his newfound abilities, Lee Rin becomes the leader of a group of night watchmen who patrol the streets from dusk to dawn to protect the people of the Chosun Dynasty against evil spirits. Moo-seok (Jung Yun-ho) is the best swordsman in the land who is the prince’s trusty bodyguard. But their loyalties will be tested when they both fall in love with the same woman – Do-ha (Go Sung-hee), the successor of the Ma Go tribe who seeks their help to protect the Baek Do mountain’s spirits. But Park Soo-ryun (Seo Ye-ji), the daughter of a court officer, will stop at nothing to marry Prince Lee Rin. “The Night Watchman,” also known as "Diary of a Night Watchman," is a 2014 South Korean historical drama series directed by Lee Joo-hwan.