Until June 8, 2008, Hiroshi Yuasa led an ordinary life, one of thousands of taxi drivers who work Tokyo's streets. But just after noon on that rainy Sunday, as shoppers thronged the streets of Akihabara, he witnessed an event that changed everything.

Sitting in his parked cab at the intersection of Kanda Myojin-dori and Chuo-dori, Yuasa watched in disbelief as a rental truck headed straight for a group of pedestrians.

"Honestly, my first thought was: 'That's a really awful driver,' recalls the 56-year-old native of Miyazaki. "Then I realized that the truck was dodging cars and deliberately trying to hit people."