Filmmaker Oliver Stone will be on Capitol Hill on Tuesday following the release of new files related to the investigation of President Kennedy’s assassination, and lawmakers want Mr. Stone himself to tell them what he thinks happened. His critically acclaimed film “JFK” has helped keep some theories alive that the 35th president was the victim of a government plot, not of a lone gunman. 

The newly released JFK files — which were filled to the brim with previously known information, along with a few primary source documents that have led to speculation by some conspiracists — will be the focus of a hearing on Tuesday. Mr. Stone will testify alongside James DiEugenio, whose book “Destiny Betrayed” served as the basis for Mr. Stone’s Oscar-winning 1991 film. Journalist Jefferson Morley, who believes the CIA was in some way involved in the Kennedy assassination, will also testify. 

Mr. Stone will appear before the House’s new Task Force on the Declassification of Federal Secrets, which was set up by the House Oversight Committee earlier this year. The task force’s chairwoman, Congresswoman Anna Paulina Luna, says Mr. Stone is pivotal to shining a light on claims that Kennedy was killed by someone — or some group of people — other than Lee Harvey Oswald. 

“After six decades of deception and secrecy surrounding the assassination of President Kennedy, the Trump Administration is lifting the veil and giving the American people the truth,” Ms. Luna said in a statement. “By investigating the newly released JFK files, consulting experts, and tracking down surviving staff of various investigative committees, our task force will get to the bottom of this mystery and share our findings with the American people.”

A member of the task force, Congressman Tim Burchett, tells The New York Sun that he and fellow lawmakers met with Mr. Stone at the Capitol on Monday night ahead of the filmmaker’s testimony on Tuesday afternoon. Mr. Burchett says that Mr. Stone is likely to present his own thoughts about the newly released files in a kind of Socratic seminar about what may or may not be true about the assassination. 

“I’d like to really just know what he wants to ask because we’re going to sit there and ask a bunch of technical questions — get lost in the weeds,” Mr. Burchett tells the Sun. 

Another Republican member of the task force, Congressman Eli Crane, would not disclose exactly what he would be asking Mr. Stone on Tuesday, though he said with a smile that he had “plenty” of questions for the Oscar winner. 

Mr. Stone has long raised questions about Kennedy’s assassination and the possibility of American intelligence agencies being involved in a broader plot given the president’s frosty relationship with the CIA. 

In a statement to the Hollywood Reporter in January, Mr. Stone said that Mr. Trump deserves praise for finally releasing the unredacted JFK files that could help create a better “mosaic” for those attempting to understand the possibility that Oswald did not act alone. 

“Those files should have been released in October of 2017. President Trump deserves further credit for going beyond that, and ordering the release of still classified files on the Martin Luther King and Robert Kennedy assassinations,” Mr. Stone said. 

“No one expects there to be a smoking gun ‘he did it’ document in those files,” the filmmaker added. “But from what previous writers understand, there will be information that will contribute to a more informed mosaic of what happened in those cases.”