The Brexit referendum divided the country. Now the division has spread to the Channel 4 film recreating the campaign.

In a grim echo of the squabbling, leaks and counter-leaks that have gripped British politics for the past two years, ugly tales of “creative differences” are emerging from the set of The Uncivil War, which stars Benedict Cumberbatch as Dominic Cummings, the director of the Vote Leave campaign.

Cumberbatch, the star of Sherlock, is said to have argued with the film’s screenwriter, James Graham, about aspects of the script, particularly its portrayal of Cummings, a prominent Brexiteer.

“Benedict was initially unhappy with the script,” a source close to the production said. “He felt that the original script showed Cummings in a positive light and he wanted