If you've ever watched someone go through a schizophrenic episode, you understand how families can be ravaged by the behavior of a person who spirals into a world of delusion and horror, augmented by flashes of what appear to be thrilling cosmic insights. The documentary, God Knows Where I Am, tells the story of one such person. Relatively late in life, Linda Bishop was consumed by schizophrenia. During a frigid winter, Bishop occupied an abandoned New Hampshire farmhouse in what was becoming a suburban neighborhood. She was about 100 yards from a neighbor but never was seen and never asked for help. Apples she found in a field became Bishop's only sustenance. Ultimately, Bishop starved to death. Directors Jedd and Todd Wider discovered a diary that Bishop dutifully kept. As a result, what might have been an anonymous death becomes the center of a sorrow-laden film that exposes the dangers of schizophrenia -- to self and others. Punctuated by Lori Singer's readings from Bishop's diaries, the movie presents a picture of a woman who expected divine intervention to save her from her four-month ordeal. I was going to call it a "self-imposed" ordeal, but that would be a little unfair. In her pre-illness life, Bishop was a good friend and a fine mother, but she lost herself to an illness that she protected from outside intrusion. True, she stopped taking the medications that normalized her life, but can a person whose mental processes become terribly distorted make responsible choices about her own welfare? Some of Bishop's diary entries have a transcendent glow that the directors try to match with visuals of the house and surrounding woods. But help -- divine or otherwise -- never arrived, and Bishop succumbed. Perspective is provided by Bishop's sister and her daughter, by townsfolk, by law enforcement officials, and by former friends. The title, taken from Bishop's writings, is instructive: Had Bishop been able to put a question mark at the end of that sentence, she might be alive today.