On the 78th floor of the World Trade Centre's north tower, no alarms sounded and no one had information about what had happened at 846am on September 11, 2001 Blind since birth Michael couldn't see a thing, but he could hear the sounds of shattering glass, falling debris and terrified people His guide dog Roselle sat calmly beside him and in that moment Michael chose to trust Roselle's judgement and not to panic This is their story