U.S. Homeland Security Secretary Jeh Johnson talks about the evolving role of his massive security efforts that encompass several governmental agencies; In a rare interview, prominent Irish Republican politician Gerry Adams addresses allegations that he was complicit in the 1972 murder of Jean McConville; Morley Safer meets up with the Wikipedians, the "persnickety," techy types who keep your favorite Internet information website brimming with data.

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