7. Episode 7 (2018)
Devil King Woo seeks Seon-mi's help in dealing with a troublesome prince who refuses to return home until he finds a runaway mermaid.
Release date: 2018-01-20
Season number: 1
Episode number: 7
Runtime: 68 minutes
Cast
Lee Seung-gi
as Son O-gong
Cha Seung-won
as Devil King Woo / Woo Hwi
Oh Yeon-seo
as Jin Seon-mi / Samjang
Lee Hong-gi
as Jeo Pal-kye / PK
Jang Kwang
as Sa O-jeong / Yun Dae-shik
Lee El
as Ms. Ma Ji-young
Lee Se-young
as Jung Se-ra / Richie / Zombie / Asanyeo
Kim Seung-o
as Lee Han-ju
Sung Hyuk
as General Winter / Summer Fairy
Yoon Bo-ra
as Alice / Jade Dragon
Sung Ji-ru
as Master Subori
Jung Jae-won
as Hong Hae-a
Kal So-won
as Jin Seon-mi (Young)
Song Jong-ho
as Kang Dae-seong
Kim Ji-soo
as Na Chal-nyeo / Ja-eun
Michael K. Lee
as Jonathan