BEVERLY HILLS, Calif. — For 30 years, Ken Burns has found the Roosevelt family “irresistible.”


Various members of the political dynasty have popped up in the filmmaker’s projects on America’s national parks, Prohibition and the Civil War. Now, Burns shines a spotlight on the family itself in “The Roosevelts: An Intimate History,” a 14-hour film debuting Sept. 14 on PBS. It will run for seven consecutive nights.


The series covers Theodore’s birth in 1858 to Eleanor’s death in 1962. In between, Theodore was elected president and his niece Eleanor married her fifth cousin, Franklin, who became president.


“I don’t know a film that has been more satisfying to me,” Burns said Tuesday at the summer TV critics’ press tour. “This is a fairly complex narrative. We’re asking questions: What is the role of government, what is the nature of leadership?”


For the film, Burns interviewed his longtime collaborator Geoffrey Ward, an authority on Franklin Roosevelt. Ward was emotionally invested in the topic, having had polio when he was 9, like FDR.


“That particular subject got me,” Ward said. “I went to the interview absolutely determined my old friend Ken wasn’t going to get me emotional, and he got me in three questions.”


Ward has spent 30 years writing about the Roosevelts, and he wanted to tell a family story in the series.


“They all talked about each other all the time and resented each other and loved each other,” he said. “There is love and betrayal and distrust, and what it means to belong to a great family.”


Each episode will be repeated the night of its original airing, and there will be a daytime marathon on the weekend of Sept. 20-21. All episodes will be available for streaming the day after the first episode airs.