The photos show a herd of zombies who never fall asleep although the sky is getting brighter with sunshine and the drama's hero, Prince Lee Chang (played by Ju Ji-hoon), drawing his sword in the darkness.
Premiered in January, the television series has drawn big attention at home and in other Asian countries for being Netflix's first original Korean drama series and a rare zombie thriller set in the Joseon period (1392-1910).
It was directed by Kim Seong-hun of the 2016 film "Tunnel" based on a script by Kim Eun-hee of the TV series "Signal.
The first season brought together Ju, Bae Doo-na and Yu Seung-ryong.
The filming of the second season began last month and it remains undecided when it will be released. (Yonhap)