July 13, 1966, was the night that introduced a terrifying new concept to Americans: random mass murder.
It all started with a knock on the bedroom door of student nurse Cora Amurao, who shared a Chicago townhouse with other student nurses.
It was 11pm, and Amurao, who had moved to the US from the Philippines less than three months earlier, unlocked the door and opened it.
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Standing there was a young blond man, Richard Speck, holding a hunting knife and a pistol. He had broken in through a downstairs window. Speaking quietly and calmly, Speck ordered Amurao and her roommate out of their room.
He gathered six student nurses together in one bedroom and bound their wrists and ankles with strips of torn sheets. When three more student nurses arrived home, Speck also tied them up.
Because Speck was quiet and calm, almost friendly, the women didn’t think he was going to hurt them. They thought he was just robbing them. He said he needed money to get to New Orleans.
"Don't be afraid," he said. "I'm not going to kill you."
But he was lying. Speck untied one of the women’s ankles and led her out of the room. Those left behind heard her muffled cries.
Amurao, still bound, crawled under a bed in the room and hid, hoping that Speck wouldn’t realise she was missing.
"I was just praying, ‘Our Father’, ‘Hail Mary’, you know," she later told ABC7.
"After he was taking these girls, one by one, outside that big bedroom, that’s when I realised he was doing something to them. But I never thought that he was killing them."
Over a period of four hours, as Amurao lay under the bed, Speck led away seven of the student nurses, strangling and stabbing them. The last of them he raped in the room where Amurao was hiding, before killing her too.