The plot is hardly new. It follows a girl named Lucy and a boy named Natsu who are both powerful wizards with a magical organisation as they undertake various mission. Despite this lack of originality the show is very good. The characters are funny yet not stupidly so and there are some nice action sequences as well. I have to say I would like a few more of these and a bit less of the comedy, but it still works. The voice actors are very good and do a great job of bringing the characters to life. There is also an excellent soundtrack throughout.
In fact just about the only thing I don't like is the slightly 'cutesy' animation but I am willing to ignore that as the rest of the show is so good.
All in all this is a good show but there are a few things I would change, still it is well worth your time.