If nothing else after seeing this show I started researching the topic of solar flares and coronal mass ejections. Both, related to things emitted by sun and having potential to affect if not disrupt communications system and other magnetic systems on earth.

The Grid is a protective covering whose origins are unknown. It starts with a murder case, which is later linked to a ghost (not literal one).

The acting is pretty good as can be expected from all the veterans. It's a returning drama for Kim Ah Joong after 5 years, so was sort of waiting for it. The cinematography especially the starting 5 minutes of first episode are mesmerising. OST wise, background music is pretty intense.

I don't see the reason for ex-spouses storyline between KAJ and KMY, but it's there. Maybe will link to main story somehow. It did link in the ending episode. As of now 8 episodes are completed. I must say it became progressively better with each episode. It has one of the most complex time travelling sequence. You might need notepad or something to keep track of past, present, future, changed past 1, changed present 2, etc.

Most of the time time travelling shows have massive loopholes. It doesn't yet.

There is a saying that a person when, preparing for a 10 minute fight, should sharpen his tools for 10 days and then fight. This show for an amazing ending gave us pretty good initial episodes. But, the problem is they didn't satisfactorily finish it. It would equal to sharpening tools in above analogy even when fight has started. Probably, there are chances of second season or something given some vastly unanswered questions at last. I deducted 0.5 due to less than okay ending episode.

If you are looking for sci-fi mystery with touch of technological advancement, this is must for you.