Ran here to see if someone picked Sisyphus and someone really did!
Anyway, I'll go with the more conventional answer Forest of Secrets because Jo Seung-woo was amazing in it and the drama itself is perfection. I rewatch it every few months just to remind myself how good kdramas can be.

I feared this day would come!

I know it’s easy to pick Stranger, but when it comes to some excellent micro acting and screen presence Life would be the one I would choose. His entire being was Gu and he was breathing life into the show. And to think he wasn’t even on screen all the time.

Also, I think I have liked him in some movies more but I am sticking to dramas here.

I'm convinced I'd never like Forest of Secrets if the leads were played by different people, so this rules the show out. Sisyphus... let's just not go there. How about Horse Doctor? Nowhere near the great show by itself but he was so darn cute there! And I'll take horses anytime over divorce cases or child murder investigations.

Dramaland is Jo Seung-woo's latest adventure. Some of his best work is on the big screen and in musicals.
Drama - Forest of Secrets 1 and 2.
Movie - Marathon.
Musical - Jekyll & Hyde.

Park Shin-hye and Jo Seung-woo are great on their own, but not paired
Well said. I have this issue in some romance pairings as well.

If I have to pick between Forest of Secret and Life, I'll remain stuck in-between. Both, just as DaebakGrits mentioned, gave social commentaries on delicate matters of the society, and corporate world. So yes, the scripts were on point. If I'll go with his performance, I'll go with Life. What's the reason? Nothing much exactly. Gu Seung-hye was a powerful human yet ordinary when he takes off his corporate suit, coupled with a good bedside manner with his family. That kinda sets him differently from his other performances that I've seen.

Forest of Secrets 1 and 2. After 4 viewings Hwang Si-mok has become a familiar friend. There's something both mysterious and reassuring about his frozen emotions. I'm sure a lot of the depth of the character is due to the wonderful performance by Jo Seung-woo.

I really liked him in God’s Gift—14 Days, but the end was so unfair >_<

So I vote for Forest of Secrets 2. I prefered the second season.

There is no competition. Stranger: Forest of Secrets.

I think Stranger is the way to go here, but here's an outside vote for Life, where he was just lights-out terrific.

I've only seen him in Forest of Secrets and God's Gift - 14 Days, and still I hate to just pick one, those are two of my favorite shows. I actually didn't mind the ending of God's Gift that much, but given that Forest of Secrets had not just a satisfying but awesome ending, no contest.

Choosing one JSW role is like choosing the best hitter on USA's WBC line-up. A buffet of superlatives, but c'mon, Mike Trout is Mike Trout and Hwang Shi-mok is...perfect.

That's not hard for me :Secret Forest is the winner!

If the quota for FoS is used up, I’ll go with LIFE ☺️

As a self-claimer fan of Cho Seung Woo, I have watched all his dramas. Some are my favorites, some I enjoy, while other I watched only to satisfy my thirst for his performance (STM, just can't wrap my head around the theme). While Forest of Secrets (both seasons are equally mind-blowing in their own way) is obviously the best out of all in terms of best drama (writing, acting, and editing), but as characters, I'd pick Life anytime of the day. Gu Seung Hyo is the man. He is the best president I've seen in Kdramas. He has good personality as well. I'd rewatch the drama just too see him light up my day with his work ethic and his love for people he cares about.

Oh, this is tough.

Despite God's Gift's infuriating ending, that drama was a very memorable introduction to the wonder of Jo Seng-woo for me. Added to that his adorable interaction with Lee Bo-young's daughter and the warm satoori his character used. There's also the superb Forest of Secrets series where he set a new standard about acting as an emotionally distant character.

But if I have to choose one ultimate role, it would be Life. His Gu Seung-hyo is a very memorable character. And it was exciting to see Jo Seung-woo flexing his acting chops to bring this antihero character to life and somehow managed to make him both complicatedly human and understandable despite his more hateful choices.

Dramas: Forest of Secrets, Horse Doctor and Divorce Lawyer Shin
Movies: Classic, Sword with No Name and Marathon

Can't we just pick Jo Seung-woo instead?

Forest of Secrets.

One of the greatest dramas, period.

This should have been the blueprint for any drama coming out of Korea going forward and has not. The drama will always be the exception and not the norm.

I'm torn between "Stranger" and "Life", but if I had to pick just one Jo Seung-woo's drama, it would be "Life".

He is just such a great actor and I know his musical background helped his acting. He is finesse at its finest. I love Divorce Attorney Shin. For an older one I too loved FOS and Life.

This is tough!

However, with the other Beanies’ deliberations, my choice is:
* Forest of Secrets 1 and 2 as greatest kdramas of all times (together with My Ajusshi) underpinned by a top notch script at world class standard
* Life as the most impressive acting piece of Jo Seung-woo for making a non-likeable character likeable. Gu is grey but black-and-white at the same time. A ruthless CEO during daytime but mommy boy by night.

Forest of Secrets, especially the first season. I love it when his feelings are trying to get in touch with him!

I totally agree with Mistyisles about God's Gift. He was so amazing in that but the last 10 minutes ruined it for me totally. I will always love him in that role though.

I loved him in Stranger 1&2 and that prompted me to watch Divorce Attorney Shin. I'm genuinely impressed by him 😌 and he's cute 😂😂

Divorce Attorney Shin