DVD: Downton Abbey: Christmas at Downton Abbey

"Some people carry more baggage than the porters at King's Cross," maintains Lady Mary Crawley (Michelle Dockery) after explaining that ruinous business with the Turkish diplomat (he perished in her bed) to her most earnest suitor, Matthew Crawley (Dan Stevens).

Poor Mary is now considered "impure" and "damaged goods", but Matthew doesn't appear to mind. Neither does her sharp-tongued granny, the Dowager Countess of Grantham (Maggie Smith, exquisite, of course, isn't she always?), or her cuddly aristocratic father, the Earl of Grantham (Hugh Bonneville), who informs her, after she's dumped the rather rude media magnate Sir Richard Carlisle (Iain Glen), that he wants her to find "a brave man, find a cowboy in the Middle West." It's 1919, and most chaps haven't survived that ghastly affair abroad and one that has, the indecently decent butler John Bates has been accused of a murder (his wife) he didn't commit. So it's fraught, clearly, for the masters and servants at Downton.

Julian Fellowes's gorgeously mounted soap opera is a suitably silly Christmas cracker, which is blessed, most of all, by Smith's arch quips. When Sir Robert claims that he doubts they will meet again, the Dowager snaps back "do you promise?" It's the best moment in this increasingly outlandish ITV phenomenon, which should be careful not to outstay its welcome...