What do you do, Jack?

What happens when you know there are people in danger, say, a bomb on a bus? You could save them, but only by putting yourself at utmost risk. Do you walk away, or do you throw yourself into the fire?

Full credit to those millions fo service people: policemen, firemen, paramilitary and military personnel, who sacrifice their lives to keep us safe. It isn't easy to go to work each morning, in the knowledge that your family might never see you again. But still these people devote their lives to making the world a better place, putting their all on the line, if needed, so that you and me can carry on with our lives as normal.