There is so much potential in the fairy tales of brothers Grimm, but everything is so poorly executed. The SFX are quite poor, the scripts are bad, the tension non-existent. The acting is OK though, and deserves some praise, especially because the actors have so little to work with.
For instance, the episode about the Pied Piper. Seriously, that was terrible in so many ways, not scary at all, very uninspired.
It's like the people behind the show had a good idea, but don't know how to actually make it work.