After watching his performance in Rebel, I can totally see him as the backbench brooding kid. He stole my heart as Mori, especially in the last episode.

I would love to see him in more things but uh, he's probably more age-appropriate to play a teacher than a high school student through an entire series. Especially if one of his co-stars is to be Kim Yoo-jung, who is actually high school age and almost a decade younger. (I trust School will actually focus on student issues and not try to pair them up like the dumb detour that was School 2015 )

I thought there already hold a audition to cast new and young faces. Kim Jung Hyun and Kim Yoo Jung are bit old for student roles.

Mori yaaaaa. ??? I want him to play a teacher, because i want him to graduate from high school drama already. Yang Se Jong who was just debuted last year (and younger than him) already playing adult role, so I want him to do the same as well.. And if he is up to play a male teacher, I want to be casted as the female teacher and be his partner. Is it possible? ??

Anyway I hope whatever decision he is making will be great choice for his career. Because he has the potential to be bigger actor if he is on the right path. He and Yang Se Jong are among rookies (and new puppies) that I am excited with their career development.

And please School 2017, less romance please! It is cute to have romance as added elements, but it won't be very cute if the love triangle becomes the centre of the drama, because if it is so, it will be just another Heirs for me.

He could play teacher ! It's always good to try different characters !

He seems a bit old for the school series but maybe the plot requires for someone older. Possibly a character that's going back to school. He was really good in Rebel and I didn't remember him in Jealousy Incarnate until it was mentioned here.

isn't he too old to be playing a highschooler opposite kim yoo jung? no offense, but i would prefer if they cast someone younger like yeo jin goo. if they're looking for rookie actors, maybe they can try lee seo won.

Yeah, I remember reading an interview of his right after Jealousy Incarnate and finding out that he's actually the same age as Go Kyung-pyo, haha. I think he could definitely pull off the rebel in the back role, but, I have to admit, I was kind of hoping he'd get to move into more age-appropriate characters after his performance in Rebel.

Yes yes yes. Sign him up!! If the cast in The Heirs could play high school characters he most certainly can too.

What? He is 27 years old?! I had no idea! I totally believed him as a high schooler In jealousy incarnate. Maybe if I had seen him in rebel, my impression would have changed. What do korean actors and actresses eat that makes them all look younger than their age?

So, I once played this game with my friends (who don't watch kdramas) where we just asked each other silly questions and when there was a question if I ever were to act in a movie, who would I want to play the male lead (yes, it was THAT game) and I told them all park bo gum and showed them his picture. They were all like 'he looks younger to you' when in actual case, he isn't! So, that's my sad little story where I realized that looks-wise, I might be noona to all my oppas.

Good choice.

He can be a rebel sunbae in school.

I like this casting choice. He looks the part, and who knows, he could even be a repeat student. lol

I have no problem him playing high school student. They are actors and they are supposed to act as fictional characters.

He's 27??? Oh my Mori Oraboni!!! ??

I really want him to take this role but now I know he is 27 I have a second thought. If this is Reply series sure he'll fit just fine but it is school series where he'll have to be high school student the whole damn time.

I hope it's about real struggles, and not something overly exaggerated because that will take me out of the drama.

As a self-proclaimed Jealousy Incarnate aficionado ??, it's an honour to hear his casting news.
. . . take a ✏️ and ✔️ this show in my ? . . .

Oui! ¡Sí! はい！好! 네! Yes!

Kim JungHyun, no matter what language you say this in, say "yes!" to this offer! Please~

I'll suspend all beliefs for you! Although seeing how you pulled off your character in Jealously Incarnate, I don't think I'll have to put much effort into it, if at all.

Omammagad!!!! I saw this and was rendered incoherent. What a nice surprise! Off to read...

He was so cute in JI <3

I loved him so much in Rebel, I don't care what role he is up for. If he signs on, I'm IN!

I never expected him to get casted for this, but I'm pleasantly surprised. He was so great in Rebel as Mori and I'm so glad he's getting his first lead role (in a full-length drama) so quickly. Please accept >.<

School 2017 is on a roll! Can't wait for this drama to secure the cast! ?

MORIIIIIII!
YES PLS

Thankfully, School 2017 is following School 2013's premise, which had no love lines like School 2015. Otherwise, a romance between a 90er & 99er is a huge no-no. I've never seen Kim Jung Hyun, but I've read good things about his acting.

He looks so good. I can see a lot of young girls fall for him if he takes the role. He has that Kim Woo Bin mean guy appeal, but better good looking. XDD

Yay for more impending smiles!!! He deserves it after all the stoic characters he's played so far.... unless.... he's supposed to be a tsundre character....

He would be perfect as a brooding rebel.

I really love his addition to the casting for School 2017! I didn't know that he is already 27 because as girlfriday said, he is still a new face in dramaland. I don't mind seeing him as a high-school student because he doesn't look that old. He really owned being Gong Hyo-jin's little brother and I can already see him as the next Gong Tae-kwang.

I hope that there not much of a romance and pour down the bromance. Please, drama gods!

Yay, I really liked him in Jealousy and Rebel so totally looking forward to him hopefully having a larger role. I was surprised when I looked him up and found out he's older than me! Although he looks young, I think I'd rather have him play a teacher fresh out of training. Him supposedly being a student in Jealousy was a bit of a stretch..

Mindblown because he's already 27? Dear lord he looks so young. He was really adorable as the protective younger bro on Jealousy so I never realized how old he is already. Wow.