The Insider.

"It's impossible to exaggerate how high the stakes were in Watergate...From the start, it was clear that senior administration officials were up to their necks in this mess and would stop at nothing to sabotage our investigation...What we needed was a 'Lone Ranger' who could bypass the administration's hand-picked FBI director and Justice Department leadership and derail the White House cover-up." W. Mark Felt, a.k.a. Deep Throat, 1913-2008.