The woman would come back to her car all laden down with packages, and when she was standing there trying to open the door, a guy hiding underneath her car would slash her ankle with a razor so she couldn't get away, then take her purse and packages and drive off in her car. Then as you reach down at your ankles in reaction to the pain, they would slash your wrists to disarm you. They then proceed to either rape or murder you, or steal your car, depending on which version you hear.
Robbery is the usual motive for the attack, but gang initiation and rape turn up in some tellings.
When it's rape, the victim is often dragged back under the car, with the deed taking place there. When the attack is part of an initiation, in some versions the victim's instinctive reaching down to clutch her injured ankle gives the prospective gang member his opportunity to cut off one of her fingers as the proof he needs. Despite the many places this legend has been, no verifiable incidents of this nature have been reported. Robberies, rapes, and abductions have taken place in shopping mall parking lots, but in none were the assailants lying in wait underneath the victim's vehicle. In 1991, when the tale was all the rage in Chicago, the police there established a hot line to give those concerned about what they'd heard a place to call and get the facts.