Perhaps the most interesting moment in the new trailer for the HBO documentary, “The Swamp,” comes at the very end when an off-camera interviewer asks Rep. Matt Gaetz, “What has President Trump done to drain the swamp?” The pause before the unknown answer tells you all you need to know about why you should watch the new doc.

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As the title suggests, HBO’s documentary, “The Swamp,” tackles the idea of who actually controls the government and how everyday people fight a battle that they might not be able to win because of special interest groups. No, this isn’t poised to be the feel-good movie of the summer. “The Swamp” is likely going to frustrate and infuriate viewers as the curtain is pulled back on lobbyists and the people who spend millions to control the politicians that people elect.

Oh yeah, and to make matters even more complicated, “The Swamp” does all this by speaking with a new crop of Republican congressmen (including the controversial Matt Gaetz) that support Trump and vowed to “drain the swamp” but have yet to do so.

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“The Swamp” is directed by Daniel DiMauro and Morgan Pehme. The filmmakers are no strangers to politically-charged docs, as the co-directors of the acclaimed film, “Get Me Roger Stone.” That film earned immediate buzz after its debut at the 2017 Tribeca Film Festival. So, it makes sense that the filmmakers are back at it, tackling another political doc that has deep ties to the Trump administration.

“The Swamp” debuts on HBO on August 4.

Here’s the synopsis:

The Swamp provides a look behind the curtain of Washington politics by following three renegade Republican Congressmen as they bring libertarian and conservative zeal to champion the President’s call to “drain the swamp,” while facing demands to raise money for their re-election campaigns and the Republican national party. Directors Daniel DiMauro and Morgan Pehme (“Get Me Roger Stone”) track Republican Congressmen Matt Gaetz (R-FL), Thomas Massie (R-KY), and Ken Buck (R-CO) over the course of a pivotal year in politics, demonstrating the breadth and grip of a system that rewards fundraising above all else, plaguing Congress on both sides of the aisle. With unique behind-the-scenes access to the inner workings of the House of Representatives amid major breaking news events, including the Mueller hearing and President Donald Trump’s impeachment proceedings, the film presents a revealing look at the core democratic institution of American government.