mandy wiener: hang on a second. could he have intentionally killed her? robyn curnow: was oscar a woman beater? and now he had killed his girlfriend? randi kaye: all of a sudden, the coverage flipped from accident to homicide. reporter: oscar pistorius, as of now, is at a police station. we started to hear reports about performance-enhancing drugs or steroids being found. and then that just started all kinds of rumors. people started to believe that this possibly was some sort of steroid-induced homicide. robyn curnow: almost immediately, oscar's brand, his image crumbled. scott roder: he went from this handsome, tall, olympian, gold medal-winning icon to a pariah. i'll never forget that oscar pistorius was on this billboard. it was advertising an oscar campaign, said, "every night is 'oscar' night." within a few hours of the story breaking, they started rolling down the billboard. robyn curnow: he'd been the face of nike. and the tagline had been, "i am the bullet in the chamber." that came down pretty quickly. reporter: this is a man who is usually bask