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In an ABC News exclusive, George Stephanopoulos goes one-on-one with WikiLeaks founder and international man of mystery Julian Assange, who has been hiding out in London's Ecuadorean embassy after fallout from his website's publication of a trove of classified U.S. material in 2010.

This Sunday only on "This Week," Assange speaks out on the latest on Edward Snowden's run from the law after his blockbuster leaks on the NSA's secret surveillance programs. How has Assange and WikiLeaks aided Snowden as he seeks safe passage from Russia? Should Snowden and WikiLeaks' partners be considered whistle-blowers or law-breakers? And what is the future of WikiLeaks as its controversial efforts remain under scrutiny around the world?

Plus, following this week's historic Supreme Court decisions on the Defense of Marriage Act and California's Proposition 8, Human Rights Campaign President Chad Griffin and National Organization for Marriage President Brian Brown come to "This Week" to debate the future of same-sex marriage in the U.S.

The powerhouse roundtable also weighs in on those landmark decisions and tackles all the week's politics, including the next steps in the battle over immigration reform, with ABC News Political Analyst and Special Correspondent Matthew Dowd; ABC News Anchor and Chief Foreign Correspondent Terry Moran, who covers the Supreme Court for ABC News ; Rep. Donna F. Edwards, D-Md.; and Wall Street Journal columnist Peggy Noonan.

Plus, Texas State Sen. Wendy Davis reflects on her epic filibuster that drew national headlines and her fifteen minutes of fame.

See the whole political picture, Sunday on "This Week."

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