A very fun and likable romantic comedy. Jun Ji Hyun is an absolute delight. Funny, fun, sexy, and just a great actress. Kim Soo Hyun is fantastic too as the very serious opposite to her, and their chemistry is so great. Without a doubt one of the best couples in kdrama. Great supporting cast too. I like how it gives Park Hae Jin a serious subplot for his character, instead of in most kdramas where the secondary male lead is just there to wallow in his own self pity of how he can't end up with the lead female. Though don't worry, he does a bit of that too XD. This drama did some cool things with it's production value. How it used it's cameras for special effects of stopping time and the other powers. I thought it was well done. The only part that really disappoints me is (minor spoiler, skip ahead to next paragraph if needed) that in one episode she falls from the stunt cable as it breaks. It is filmed and planned out so dis-believably and just terrible. Even with the height, she falls on a pad and caught by a guy and both end up in small comas? WTF. Other than that I don't have any big complaints with this drama. Though I do have mixed feelings with the ending. (Spoiler, skip ahead again if you haven't watched) The ending is perfect in many ways. If it ended up being too happy and easy with everything resolved, then it would have been a bit too much fanservice and unrealistic (ha! I say that about a drama that is about an alien lol), it's just that it leaves unanswered questions. And the biggest one is how long can they really be happy together when we know the issue of her aging while he doesn't is still up in the air? I know not everything can end perfect, but it kind of makes it a bit sad doesn't it? Anyways, overall a great drama with some great actors. Be prepared to cry. I cried so much at the end of the second to last episode and at the beginning of the last episode, that I couldn't even produce any more XD. But that's what makes it good, right?