This is a very sweet episode, Spot is adorable! Ariel hiding him in the palace was very funny and I loved the whole thing, especially Spot coming out and singing. Ariel's father was very harsh on her though.
This episode seems to take a much longer time then it really does, they pack alot into a half hour. It seems to last a long time, especially when you get to the shark battle in the end.
Nice way to end it with Spot saving Ariel. Having to let him go almost set me crying when I first saw the episode. However, it was the right thing to do.
Lovely intro to all characters, you really get to see their personalities clearly, very little or no acting out of character which is always essential for a good pilot episode.