With its portrait of upstairs-downstairs life in the last golden years of Edwardian splendour, Downton Abbey is the most popular period drama since Brideshead Revisited.
The series came to a typically dramatic end last night, culminating with Cora's miscarriage, John Bates' survival in his job and, oh-so ominously, the announcement that the First World War had begun. But having picked up audiences of more than 11 million at times – and prime advertisement sales with it – ITV has signed up Oscar-winning screenwriter Julian Fellowes for a second series.
It is not just the broadcaster benefiting from this unexpected runaway success, however. The drama is lined-up for a lucrative slot on US network NBC, potentially making it one of the most prominent shop windows for a new wave of British acting talent in years. So could Brendan Coyle be the next Colin Firth?
Mr Coyle, who plays war-wounded valet John Bates, is no raw young buck. He turns 47 next month, having fashioned a moderately successful career based on British TV staples such as Waking The Dead and Lark Rise to Candleford.
Fans of Downton Abbey are hoping they will be seeing much more of him in future – perhaps providing competition for the roles of English heartthrobs that Mr Firth has made his own since his breakthrough in the BBC's 1995 Pride and Prejudice.
For some of the other stars of the series, their first steps to fame across the pond are under way. Michelle Dockery, the 28-year-old who plays Lady Mary Crawley, will next year appear in Hanna, a hotly anticipated thriller about a 14-year-old assassin.
Dan Stevens, who plays the heir Matthew Crawley, has just completed filming Vamps, a horror comedy about female vampires seeking love in New York. And Rob James-Collier, formerly of Coronation Street but now best known as gay footman Thomas, has a turn beside Billy Zane in action movie Mercenaries.
Even familiar face Hugh Bonneville, a so-called "mums.net pin-up," could see a boost to the kind of roles and scripts he can attract too. The man who took Fellowes' lead role as the Earl of Grantham is one of the hardest-working actors in British film and television, but a move across the Atlantic could be in the offing for him as well.
Success on the small screen in the US can often prove a powerful springboard to work in the cinema. Tom Hooper, the English director behind The King's Speech – a film hotly-tipped to land major awards at next year's Oscars – did his career no end of good by working on John Adams, a much-lauded drama series about the life of the second American president. Mr Hooper has come a long way from directing episodes of Byker Grove and EastEnders.
If there is one cast member whose career trajectory will remain steady, of course, it is Dame Maggie Smith. With seven Baftas, two Academy Awards, two Golden Globes and one Emmy to her name, thanks to films as highly regarded as Tea With Mussolini and A Room With A View, she hardly needs a boost to her profile.