Both dramas are OCN master pieces with a fair share of dark content. Don't expect too many 'nice' scenes since there are not any...

Both dramas show the story of resistance fighters in Korea in the 20th century and do a pretty good job at that.

Both dramas have a big amount of a psychological touch to it, giving an example of how the human brain can be influenced by mere wrong doings of someone else.

They both have strong female leads that know what they want and are fighting for it! Both stories revolve around an office/boss - employee romance.