This is just one of those dramas you have to watch. It's that good. It's the heart aching poetry of how history repeats itself, and falling to one's fate. Gu Family Book has a depth you rarely see; there are so many levels to the plot, each enhanced by a spectrum of emotions and feelings. As a warning, this series takes a hatchet to your feelings. While the feels are proof of a phenomenal drama, you may need to do something like hold kittens or let puppies lick you to make everything okay again. While some scenes are arguably dragged out too long, I was amazed about how much happens in every episode. I'd get to the end of one and be shocked at how much actually took place in just that one hour. These are not a boring 24 episodes. Despite how much I adored this drama, the ending has the potential to ruin the entire series. I really had to sit down and think about if the final twenty minutes really lowered my entire opinion of this series (the other 23 and a half hours of it). Avoiding spoilers, I believe Gu Family Book would have had a much, much stronger ending if it had ended thirty minutes into the final episode. While it would have been much sadder, by ending on a promise it would have been more beautiful. The ending almost mocked the rest of the series with it's casual atmosphere. Among my issues with the ending was the fact that there was a significant lack of closure for the vast majority of the characters. Gu Family Book focuses so much on the characters' interactions with one another and their growth as a whole that to not know what happens to them gives you a very incomplete feeling. On the more technical aspects, my only complaint was the supernatural effects (this includes the design of the gumiho's divine creature appearances). They were... somewhat cheesy and contrastingly cheap in comparison to the effort put into the costumes and sets. What I considered the worst part was that they threatened to ruin many serious and emotional scenes. While I can't speak to the historical accuracy of the setting and costumes, they were beautifully done and obviously had a great deal of effort put into them. The music beautifully accented the scenes-- moments where I was close to tears, the music often pushed me over the edge.