Although it is quite a quick watch, I'd say it is still long. The plot being a mystery for over half the time makes it frustrating; since they did nothing to lay it out but gave us the answer all in one or two episodes. The character 'Xiang Ze Yi' has small character development despite having been through more than others. I find myself questioning the title of the series "?????" many times too, but since its called 'Where the lost ones go' in English, its different. Also, since it is available in YouTube, I find myself turning it on at the speed of *2 due to the slow plot development. I really liked the start of the series however, before the so called mystery plot got hidden too long. I would not say its not worth a watch though, I like how it has its own essence unlike some other dramas, but for me it is still a stretch; but hey, I did finish the series in a few days, so have a go!