The ending is holy good. I don't know why it's getting low ratings. But I can clearly see the writer's vision. The Adamas is not like typical crime, thriller dramas. It's on another level of conquest. And I can very much guess there will be a season 2; sooner or later they'll announce it.
*Don't Judge my Opinion, everyone's taste & mind is different. It's not how we see it; it's how it's made.
I don't care about ending as I didn't even watch it yet. But still, I want season 2.
Adamas has not been renewed for a second season as we write this article. However, the industry prefers to wait until it decides on renewal. Most K-Dramas tend to enjoy a single-season story and wrap things up conclusively by the finale.
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*Don't Judge my Opinion, everyone's taste & mind is different. It's not how we see it; it's how it's made.
Source: https://list23.com/1050356-will-adamas-season-2-be-renewed-or-cancelled/