First, let me address the myth that Time Travel shows are banned in China. That is not true. What is banned is any show where the past is a good place to live, especially if the past is better than the present. Of course, reincarnation is actually banned, but that is a different story.
So, what would happen if you died and your soul traveled back in time to when you were 18 or 20 years old to live your life again? Would those decades of experience help or hurt you? Would history play out the same again or would you attempt to change it? Would this change you and your decisions? What if you weren't the only one? What if you were a member of the royal family?
This is the essence of this drama. I generally found it well done and interesting. I did watch it to the end, which I don't do with shows that bore me. I did debate between giving it 7 or 8 stars as there are obvious flaws and mistakes. But, ultimately I decided on 8 because what show doesn't have flaws?
There are several unexpected twists in the show, I would have liked to see more. There is a sense of humor in the show, where the main characters can say something to each other, then laugh at what they said. I liked that, the ability to laugh at yourself is always appreciated.
Overall, worth your time to watch. I suggest you watch at least the first three episodes, before you decide if you want to keep watching it.