Die drei ??? Valley of horror

A woman awakens at the steering wheel of her car in the middle of the Magic Mountains. She has no idea where she is; her head aches. The only thing she can remember is that an Indian wearing an eagle-mask yanked her out of her car in the middle of the night. The police have doubts about the woman's sanity, but die drei ??? believe her. Fearlessly, they make their way to the Valley of Horror and experience the worst night of their lives.