Former Congresswoman Gabrielle Giffords-- disabled from an assassination attempt in Tucson, Arizona-- and her husband, astronaut Mark Kelly, share their impassioned argument for responsible gun ownership and more responsible gun control laws, despite being gun owners and staunch supporters of the Second Amendment themselves.

The line in the sand -- Gun country -- Active shooter in Tucson -- "You failed!" -- The NRA : from marksmanship to muscle -- Newtown -- How the NRA controls Congress -- NRA, Inc. -- A broken system -- Guns don't kill people, people kill people -- Long odds -- Senate showdown -- The way forward.