I don't know about the title, "The Witch" ? This film is in no way near about witchery or witches, it is about about a bunch of kids who were experimented upon and "given" special powers.
The first hour of the movie is boring, to say the least. But after that, if you are still watching, then this is when the "fun" begins.
Then the viewer begins to understand what's going on. And the revelation of the lead characters' plan.
Lots of action ! Not bad really .