ABC News April 26, 2015

President Obama Reveals Surprise Guest at White House Correspondents' Dinner

WATCH: Obama's Anger Translator Speaks the Truth

President Barack Obama brought out a surprise guest during his monologue at the White House Correspondents' Dinner on Saturday night.

Obama had Keegan-Michael Key, of Comedy Central's "Key and Peele," come on the stage in character as the president's anger translator Luther. As the president rattled off issues like global warming and campaign finance, Luther interjected, giving the audience a clue as to what Obama was really thinking.

Luther even got to sneak in a "Game of Thrones" reference tied to presidential candidate Hillary Clinton.

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When Obama mentioned that the Koch brothers would be putting up a billion dollars for their favorite conservative candidate, Luther said no one should worry -- because Hilary Clinton is running.

"She's gonna get all that money -- ooh, Khaleesi is coming to Westeros," he said.

Watch the entire exchange above.