Regardless of the risks involved, there will always be filmmakers who want to turn a successful TV show into a big screen blockbuster. The truth of the matter is however, very few get it right. For every Mission: Impossible there are hundreds of Charlie’s Angels, The Man from U.N.C.L.E and The Dukes of Hazzard etc, that get it oh so wrong.

One TV title that initially wouldn’t necessarily be considered a contender for a big screen make-over is ITV’s Downton Abbey. But one should never underestimated class.

It’s 1927 and very little has changed at Downton Abbey, the one noticeable exception being that Mr Carson (Jim Carter) has retired from his duties, with the young Thomas Barrow (Robert James Collier) replacing him as head butler.

But when the Crawleys receive a letter, declaring that the king and queen are to stay at Downton Abbey, it sends a veritable frisson of excitement throughout the entire household.

Their impending arrival brings with it a certain amount of commotion. To stem the impending panic, Lady Mary (Michelle Dockery) decides to bring Mr Carson back to take control, much to Mr Barrow’s disappointment.

He’s not the only one to feel disappointed, as the royal visit brings with it an entourage that takes the staff by surprise, diminishing their own roles within the house. Not to be outdone, the staff decides to take matters into their own hands with a growing revolutionary spirit brewing downstairs, which brings with it a type of polite chaos to Downton.

The key to a successful transfer from small screen to the big, seems to be to keep as much of what made the series a success intact for the film. Downton Abbey the film does just that. To that end, the film is a pleasing homecoming; not only do all of the show’s familiar faces make an appearance, which thankfully includes Dame Maggie Smith as the prickly Violet Crawley, but it’s also penned by the creator’s hand, Julian Fellowes. With Fellowes’ script, not only do you get a gentle continuity of personalities, you've also an assured guarantee that the film delivers on the show’s legacy.

Add to that the fact the director Michael Enger helmed a number of episodes of the show itself, and what you get is a delightfully cosy extension of the TV series.

Yes the larger budget ensures that Downton looks magnificent from every angle, including no doubt a number of spiffing drone shots, as well some extra cash to spend on a few more background artists milling about both on the streets and below stairs, but it doesn’t take away from the quaint intimacy that the show developed.

Audiences around the world certainly found it most agreeable; with a respectable budget of around $20 million, the film took almost $200 million at the box office. That’s not only expected to put a large grin on Lord Crawley’s face, it also opens the rather stately door to further visits to Downton on the big screen.

There was something delightfully warm and reassuring about the TV show, and this film is no different. Some may well consider it old fashioned and twee, but In increasingly uncertain times, Downton Abbey is the perfect comfort watch, rich with a sense of familiarity, history and charm, making it an extremely worthwhile visit for one and all.