It's a while ago, when I saw the first season, but I really liked this Special.
So I think if you've seen the previous episodes, it'll be interesting, too. The'll show some scenes in a different viewing point then Season 1. The story's well told and I enjoyed it very much.
Thanks to it, I really could remember the key points of the series, and I'll like to watch the second soon, would even work as preperation to look the second season, but better for sure watch the full first season, it's worth. :D