Edit : Soompi said it wasn' a dream. Imma just go with that!
Ending: Yoon Sung loses JinPyo/FakeDad and iI believe dies with respect for him as he said he was city hunter; thus saving Yoon Sung. He and Nana share this moment where they see each other and stare lovingly at each other, and next we see him driving. Is this a scene into a new series? I really hope so!! I don't know what else it would be.
Oh! And his mom and Ahjussi leave for the US and her co-workers get married(they're so cute lol). And she lets her dad die.
Plot: Lee Yoon Sung is stolen as a baby and riased by the sole survivor of a disasterous military mission to one day take revenge on 5 politicians.
Why: LEEMINHOANDPARKMINYOUNG are amazing actors. No, they really are. It could've been totally different if there wasn't the level of great acting shown in this drama.
Watch time: Since it's ended, You could probably go through the 20 episodes in less than a week no problem. It's very addicting.
I'll do a nice, more in depth one with pics and errthing when I get time ^-^