Scariest thing? My ex.
Scariest things the slightly more relative: Taman Shud case of the Someton Man (technically it should be "tamum"). I mean, at first it just sound like a unidentified body case,. but then it twist and turns. Case in point (copied from wikipedia):
On 6 June 1949, the body of two-year-old Clive Mangnoson was found in a sack in the Largs Bay sand hills, about 20 kilometres (12 mi) down the coast from Somerton.[71] Lying next to him was his unconscious father, Keith Waldemar Mangnoson.[72] The father was taken to a hospital in a very weak condition, suffering from exposure;[71] following a medical examination, he was transferred to a mental hospital.[73]
The Mangnosons had been missing for four days. The police believed that Clive had been dead for twenty-four hours when his body was found.[74] The two were found by Neil McRae[75] of Largs Bay, who claimed he had seen the location of the two in a dream the night before.[76]
Following the death, the boy's mother, Roma Mangnoson, reported having been threatened by a masked man, who, while driving a battered cream car, almost ran her down outside her home in Cheapside Street, Largs North.[15] Mrs Mangnoson stated that "the car stopped and a man with a khaki handkerchief over his face told her to 'keep away from the police or else.'" Additionally a similar looking man had been recently seen lurking around the house.[15] Mrs. Mangnoson believed that this situation was related to her husband's attempt to identify the Somerton Man, believing him to be Carl Thompsen, who had worked with him in Renmark in 1939.[15]
J. M. Gower, secretary of the Largs North Progress Association received anonymous phone calls threatening that Mrs. Mangnoson would meet with an accident if he interfered while A. H. Curtis, the acting mayor of Port Adelaide received three anonymous phone calls threatening "an accident" if he "stuck his nose into the Mangnoson affair."
Soon after being interviewed by police over her harassment, Mrs. Mangnoson collapsed and required medical treatment.
But that was only one of the strange occurrences related to the case, and it's connection the Rubaiyat of Omar Khayyam. I have a copy of that book btw.
Not sure why this freaks me out, but it does when I read about it.