Helen Hunt says Nancy Campbell, the fictional reporter she plays in the war drama “World on Fire,” is based on two different real-life journalists: William Shirer, who chronicled Hitler’s rise to power for CBS Radio, and Claire Hollingworth, the Daily Telegraph reporter whose “scoop of the century” broke the news that Germany invaded Poland — triggering World War II.

“William Shirer wrote [the 1941 bestseller] ‘Berlin Diary’ and literally all my research was in that book, which told what it was like to be  in Berlin in the three years leading up to the war,” says Hunt, 56. “That book landed in my lap thanks to [series] writer Peter Bowker. Shirer was hearing all the propaganda and being called to press conferences to hear Hitler paint his situation as though he was the one being victimized.

“Claire Hollingworth … was a relatively new reporter living and working on the Berlin-Polish border,” she says. “She went out to get coffee one day and saw German tanks hidden behind burlap sacks that were hanging on a fence. She went home and called her paper and said, ‘It’s happening tomorrow’ and they said to her, ‘You better be sure — we’re putting it on the front page.’

“I remember reading that she called her paper the next day and held the phone out the window [so they could hear the gunfire and chaos] and said, ‘It’s happening right now!'”