During the Joseon dynasty, Lee Rin, a prince who lives a lonely life outside the palace since childhood, even though he is born in the direct line of descent. Lee Rin has wealth and good looks but lives as a rebel to overcome internal struggles. Due to the fact that he can see ghosts, Lee Rin hides his secret and pain from childhood with a smiling face and playful behavior. After meeting Do Ha, Lee Rin joins the team of night watchman and becomes a true prince after seeing the lives of the citizens as he helps get rid of the ghosts. The night watchman is crime prevention squad that used to patrol the streets from 9 to 5 at night to catch ghosts.
在朝鲜王朝，李林（Lee Rin）王子自小就生活在宫殿外，尽管他出生在世系的后代，但他一直在寂寞的生活中。李琳（Lee Rin）拥有财富和外表，但他是克服内部斗争的叛逆者。由于他可以看到鬼魂，李琳以微笑的脸和嬉戏的行为掩盖了童年时期的秘密和痛苦。与Do Ha会面后，Lee Rin加入了守夜人团队，并在看到市民的生活后成为一名真正的王子，因为他帮助摆脱了幽灵。守夜人是预防犯罪小队，曾经在晚上从9点巡视至5点巡逻，以捉住鬼魂。