I loved the idea behind the plot line. The idea of a nearly indestructible alien stranded from his home planet, forced to wait 400 years in order to return to his home planet. However, I think the director could have explored the questions he raised in his drama. Also, the last episode was a TERRIBLE ending. It resolved NOTHING and was just a pile of romantic rubbish.The casting, on the other hand, was beautiful. Kim Soo Hyun was perfect.