One of Downton Abbey's main characters could soon quit the show in order to concentrate on trying to forge a career on Broadway.

Actor Dan Stevens, 29, who plays Matthew Crawley, heir to the Downton estate, has reportedly refused to sign up for a fourth series next year.

Later this month Mr Stevens will appear in Broadway play The Heiress.

He said: ‘New York for me is going to be one big adventure. I will be taking the whole family out and we will be there for six months.‘I don’t know if I will be returning to Downton.’

The loss of one of their pivotal stars would be a blow to Downton Abbey’s producers.

But his departure would present an even greater challenge to the show’s scriptwriter Julian Fellows.

As the heir to Lord Grantham’s house and fortune, Matthew Crawley is integral to the show’s plot.

The drama’s credibility has already been stretched in recent weeks with its fourth premature death in just three series.

Lady Mary’s sister Sybil -played by Jessica Brown-Findlay - passed away in a fit of convulsions as her family wept by the bedside.

Previous episodes have seen young fiancée Lavinia Swire succumb to a deadly flu virus, footman William Mason die in the Battle of the Somme, and Turkish diplomat Kemal Pamuk suffer a fatal heart attack in Lady Mary’s bed.

An ITV spokesman said: ‘We don’t discuss an actor’s individual contract or storylines.’

Mr Steven's departure would be a double blow to fellow Downton star Michelle Dockery, who plays his on-screen wife.

In real life the 30-year-old actress - who plays Lady Mary in the hit ITV1 series - has ended her five-month relationship with fellow actor Joseph Millson.

Miss Dockery, 30, started dating Mr Millson, 38, after she split from her long-term boyfriend Trent Davies earlier this year.

Last month, the pair attended the Emmy Awards in Los Angeles, where she was nominated for Outstanding Lead Actress in a Drama Series.

【娱乐快讯】《唐顿庄园》又爆出重磅消息！在第三季失去三小姐Lady Sybil 后，饰演男主角“大表哥”的丹·史蒂文斯昨日承认，他没有跟《唐顿庄园》剧组签约第四季，这也就意味他饰演的角色“Matthew Crawley”将缺席第四季。没有了大表哥的《唐顿庄园》剧情将如何继续？

据悉，丹·史蒂文斯做出此决定主要是因为自己的百老汇事业。下个月他将在百老汇舞台上出演戏剧《女继承人》。丹·史蒂文斯的退出将给编剧朱利安·费罗斯带来严峻的考验，剧中他的妻子Lady Mary戏份也必然受到影响。而在现实生活中，饰演 Lady Mary的女演员米歇尔·道克刚和交往五个月的男友分手。