One of the best dramas I have seen. The actors all did an amazing job (esp. Chen You, Alyssa Chia and Chris Wu), the story was poignant and relevant in our world (particularly in the West where gun violence is so common), the production value was decent and the OST wasn't bad either. 9.5/10.
P.S. Yeah, it's bit heavy like the comment below mentioned but all of the characters really care and look out for each other and it's an happy ending too :)
A bit slow and it did drag towards the later episodes but I would still recommend watching this drama. The acting by everyone was amazing and the show had very important themes and messages. The cinematography was also great. 8.5/10.
I know some people have doubts about Taiwanese dramas but this one was on par with or even surpasses Kdramas. Simply an amazing show, I literally cannot sleep because I'm so invested in the story.
4 
Her acting skills are always excellent, but special mention for her acting in The World Between Us!
P.S. Yeah, it's bit heavy like the comment below mentioned but all of the characters really care and look out for each other and it's an happy ending too :)