The documentary footage was subpoenaed by the House Select Committee investigating the Capitol riot and includes 11 hours of interviews with former President Donald Trump and his family. Alex Holder, the filmmaker, also provided the panel with hours of related footage, including some shot on 6 January at the Capitol.
The trailer shows Mr Trump, Ivanka Trump, and Donald Trump Jr and Eric Trump sitting for one-on-one interviews with the filmmaker.
In a series of quick-cut clips, Ms Trump can be heard saying that her father is "honest" and "is who he is."
Donald Trump Jr says his father thinks "everything he's doing is right" before Mr Trump's voice cuts into the trailer.
CNN just played the first footage from that Trump documentary that has come up at the January 6 hearings pic.twitter.com/PLhzoR4TGt
— Aaron Rupar (@atrupar) June 23, 2022
"I think I treat people well unless they don't treat me well, in which case you go to war," Mr Trump said, his voice playing over footage of the Capitol riot.
Near the end of the trailer, Mr Holder asks Mr Trump if they can talk about 6 January. Mr Trump replies “yep.”
The existence of the documentary came as a shock to many of Mr Trump's former aides and staffers.
"What the f*** is this?" one former aide reportedly told Rolling Stone.
According to The New York Times' Maggie Haberman, few within Mr Trump's inner circle knew of the documentary's existence, likely because it focused on the former president and his children rather than his top officials.
The documentary appears to be headed for Discovery+, the Discovery channel's streaming service, sometime this summer. No date was attached to the trailer, only a vague "coming soon."
“Alex Holder’s ‘Unprecedented’ three-part docuseries about the 2020 election will be released on discovery+ later this summer. Featuring never-before-seen footage of the Trump family on the campaign trail and their reactions to the outcome of the election, the docuseries will offer intimate and unprecedented interviews with Trump, his family and others who were in the White House,” a Discovery+ spokesperson said in a statement to CNN.
The House Select Committee requested all of Mr Holder's footage that contained interview with Mr Trump and his family, as well as any footage of or discussing the Capitol riot.
Mr Holder agreed to the panel's requests and handed over the footage. He said in a statement that he would cooperate fully with the House Select Committee.