The movie spends considerable time tagging after the fast-moving Mr. Stone, tracking him from event to event, car to home to microphone, as when he swans into an outdoor rally during the 2016 Republican National Convention that registers as pro-Trump, though perhaps more anti-Clinton. There are signs and people milling about wearing shirts emblazoned with the words “Hillary for Prison”; for his part, the uncharacteristically underdressed Mr. Stone seems almost naked in a T-shirt with Bill Clinton’s smiling likeness and the word “rape.” The movie doesn’t at this point identify Alex Jones, the radio host and conspiracy theorist (the “Pizzagate” hoax), who can be seen hovering at Mr. Stone’s side.

Mr. Jones isn’t formally identified until well into the movie, a careless, exasperating decision. Like other documentaries, this one crams found footage into punchy montage sequences held together by (not always identified) voice-overs. The problem with this clip-art approach is that it tends to turn history into cultural wallpaper, as in the section featuring images of the unnamed Julius and Ethel Rosenberg, who — with the help of Roy Cohn — were executed in 1953 after being convicted of conspiracy to commit espionage. In other areas, the lack of specificity raises questions that remain unanswered, as when an image of the Pentagon flashes by without explanation.

Movies about colorful characters, be they saints or sinners, are often hijacked by their subject, so it’s unsurprising that Mr. Stone, with his bespoke suits and Nixon tattoo, owns this one from the get-go. An energetic tour guide and three-ring circus of one, he seems happiest in front of the camera, which in turn eagerly laps him up. It’s a familiar interdependency and, at times, this movie suggests that his most obvious talent is for self-promotion, one that’s been aided by the attention of the news media. Among the few journalists who seem to have really gotten under his thick skin was Wayne Barrett, an investigative reporter for The Village Voice who died in January.

Mr. Stone has been providing journalists with copy for years. In 1985, Jacob Weisberg profiled him in The New Republic (“The State-of-the-Art Washington Sleazeball”), drawing a line from Mr. Stone’s lobbying work to those Reagan aides — Lyn Nofziger, Michael Deaver, Lee Atwater and Ed Rollins — who “have abandoned helping Reagan make conservative ideas reality in order to sell their connections to the highest bidders.” The journalist Jane Mayer (“Dark Money”) effectively picks up that same thread in the movie when she says, “Lobbying had been considered kind of a sleazy business, but Roger Stone unabashedly came out and said, ‘I’m going to make a pile of money off of this and no apologies.’”