Spoiler alert: key plot details follow

Seth Rogen was forced to tone down a Kim Jong-un death scene for his new comedy The Interview following a personal intervention by the Japanese head of Sony’s parent company, according to hacked emails.

Studio boss Amy Pascal relayed a series of requests to Rogen from Kazuo Hirai, chief executive officer of Sony Corp. The actor and director, whose movie centres on a farcical US plot to assassinate the North Korean leader, was reluctant to agree to edits but eventually bowed in the face of extreme corporate pressure.

“This is now a story of Americans changing their movie to make North Koreans happy,” he complained, in an email dated 15 August. “That is a very damning story.”

But Rogen later emailed to confirm he had removed some gory details, including “flaming hair” and a wave of “head chunks” from a scene in which Kim Jong-un’s head explodes after being struck by a tank shell.

Pascal pointed out that she had not previously received a single word of direction from Sony’s corporate parent company in the 25 years she had worked for the studio. “This isn’t some flunky. It’s the chairman of the entire Sony Corporation who I am dealing (with),” she said. “I haven’t the foggiest notion how to deal with Japanese politics as it relates to Korea so all I can do is make sure that Sony won’t be put in a bad situation, and even that is subjective.”

The emails are among a tranche of more than 33,000 communications released by hackers who broken into Sony’s servers last month. The architects of the cyber-attack, who call themselves Guardians of Peace, have demanded Sony can The Interview or face further unspecified consequences. They have already leaked several unreleased Sony blockbusters to torrent sites.

Pascal and producer Scott Rudin hwere forced to apologise after it emerged they joked about Barack Obama’s race and presumed taste in movies in an email conversation, while five of Sony’s upcoming films have been released onto free piracy sites before they have taken a single dollar at the box office.

In related news, The Interview is now unlikely to be released at all in Asia, according to the Hollywood Reporter. A Sony source told the US trade bible: “It was never going to be released in Japan. Like some of those R-rated comedies that go down very well in the States, they don’t work here and don’t get released.”

The Interview stars Rogen and James Franco as two journalists charged with carrying out the killing of Kim Jong-un, a storyline which prompted North Korean officials to complain to the United Nations in July and prompted state media warnings of “merciless retaliation”.

The film, co-directed by Evan Goldberg and also starring Lizzy Caplan, remains on course for a release in US cinemas on Christmas Day, and in the UK on 6 February.