THE SHORT VERDICT:
Show is tightly paced, pretty well-written, and manages solid cliffhangers and some good plot twists, through its run. Just be prepared for a fantastical set-up (robots, after all), with melo lashings in somewhat substantial measure.
With the right lens, though, this show is highly enjoyable. I found myself looking forward to new episodes of this one, more than I did with most other shows on my drama plate at the time.
Seo Kang Joon is absolutely fantastic in this, demonstrating acting chops that I never knew he had. Show is worth the watch just to see him in action.
A ride more rollicking than I first expected or imagined.