Yes, it's Hansel and Gretel. Nothing is changed. Well, the names of Hansel and Gretel are changed. Oh, and the witch is now a Krillitane. But otherwise, it's the same story. Kids in the woods find a gingerbread house, the owner captures them, they kill the owner and escape. The Krillitane is a fine choice to substitute for the witch, but really, I don't know what the point is. Maybe a fairy tale to read to kids who like Doctor Who but don't already know the Hansel and Gretel story?