tvN’s upcoming drama Black Dog has unveiled its first teasers and poster featuring the show’s lead Seo Hyun-jin.
Black Dog tells the stories of teachers at a private high school and the pressures they deal with as they go about doing their jobs. It centers on an idealistic teacher, played by Seo Hyun-jin (The Beauty Inside), who is dedicated to her job.
Other cast members of the drama include Ra Mi-ran (Melting Me Softly), who plays a career counselor and Seo Hyun-jin’s mentor, and Ha Joon (Arthdal Chronicles), who takes on the role of a Korean teacher who is beloved by students and stays away from office politics.
Black Dog‘s first teaser shows Seo Hyun-jin standing in front of a tunnel. She thinks back to a memory of an accident when she was in school and remembers a teacher saving her life. It is revealed that this selfless act by her teacher, played by Tae In-ho (My Fellow Citizens), inspired her to become a teacher herself.
The second teaser has a more cheerful vibe and introduces Seo Hyun-jin’s and Ra Mi-ran’s characters. There is a world of difference between them as teachers—while Seo Hyun-jin, new to the job, is nervous and unsure in front of students and gets caught in many hilarious situations, counselor Ra Mi-ran deftly handles the affairs at the school and also encourages Seo.
Meanwhile, in the first poster for the drama, Seo Hyun-jin is seen climbing up the stairs holding books, possibly on her way to a classroom, while Ra Mi-ran looks at her from the upper floor with a welcoming smile. The poster signifies the difference in the experience between these two teachers, as well as the mentor-mentee relationship between them. The text on the poster says, “I thought I would know everything when I became a teacher,” signaling the journey of growth that Seo Hyun-jin will undertake in the show.

Black Dog is directed by Hwang Joon-hyuk and written by Park Joo-yeon, who teamed up last year for the drama special The Woman Who Makes The Last Meal. It will replace Moon Geun-young’s Catch The Ghost on December 16.
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