Beware of the Slenderman was well-received at its world premiere at Austin's SXSW Film Festival. It is a true crime story about two 12-year-old girls who attempt to kill another young girl. The film, which will be broadcast in the near future on HBO. They are telling an intriguing story, but they try to tell too many stories. It seems obvious from the beginning that the girls are suffering from severe mental illness and that's the primary explanation for their violent behavior. Their behavior appears to be linked to mythic internet creature called Slenderman. Some of the most intellectual parts are their explorations of myth and folklore and how people come to rely on them. But then they seem to want to blame mental illness on misuse of the Internet. They don't seem to realize that there are mentally ill people who acted out violently long before there was the Internet. Long before "Slenderman" there were young people with psychological issues. And then spend a lot of time talking to the kids' troubled parents who feel responsible. And they explore the court procedures around their story. And they keep going on and on. They can't really figure out what story they are telling. At two hours the film simply goes on too long and goes off on too many tangents. They repeat their themes over and over without really getting that far. In the end, they could have told this troubling story a lot better and lot more simply. It is still an entertaining story, but it could have been a lot better.