It is way more darker series when compared to the first season with it focusing on one multinational company that happens to be focusing on those that are considered "forbidden science" in real world, while remaining relevant to the theme of the drama in general, with a few new characters added in the season.

There is a lot of gore, bloody and even violence scenes across the series (can be very horrible or shocking to watch for some), so for those who are afraid to these scenes, you should avoid watching this. There are a lot of similar dramas out there there has less of these scenes.

Otherwise, I recommend you to watch the drama (alongside the first season). Even without watching the first season, it can be still enjoyed as a standalone series as both seasons are independent with each other, just with different topics.