Downton Abbey Christmas Special, ITV1

Though the wind had wailed mournfully through the plot-holes of the second series of Downton Abbey, writer Julian Fellowes was in his element for this two-hour Yuletide spectacular. With the characters in place and a cluster of storylines tantalisingly in play, it boiled down to a grand game of tying knots, building climaxes and sawing off the loose ends.

It was a year on from the end of the Great War, but while Matthew Crawley was miraculously restored to full mobility (and virility) after his brush with paralysis, the murder trial of Mr Bates (Brendan Coyle, pictured right) hung over the supposed festivities like a cloud of mustard gas from the Western Front. We've been kept in the dark about exactly how his first wife met her end and everyone at Downton has been convinced of his innocence, but given the chance to give him a helping hand in court, his alleged allies seemed hell-bent on sending the poor fellow to the gallows.

O'Brien (Siobhan Finneran) recalled helpfully how he'd returned from visiting the deceased with a scratch on his cheek, and reported to new wife Anna that the meeting had been "worse than she could possibly imagine." Mrs Hughes (Phyllis Logan) said he'd called the dead woman a "bitch" and threatened to hit her. Even the Earl of Grantham himself (Hugh Bonneville) couldn't help recalling how Bates had wished that she was not only his former, but his late wife. With friends like that, it was scarcely to be wondered at that the judge had no hesitation in whipping on the black cap and dispatching the doleful Bates to the hangman.

The other big theme went rather better. Lady Mary (Michelle Dockery) was rapidly growing sick of the sight of her husband-to-be, Sir Richard Carlisle (Iain Glen), and his "I dragged myself up by my bootstraps unlike you silver-spoon toffs" routine was beginning to sound increasingly like Monty Python's Four Yorkshiremen. It suddenly dawned on everybody, even Mary herself, that a few weeks of banner headlines about Posh Totty Bonks Dead Turk would be preferable to a lifetime of watching one's breath form icicles over the breakfast toast and marmalade with the chisel-faced Sir Richard. The Earl told Mary to tell him to publish and be damned because "I want a good man for you, a brave man!" (reader, how we cheered). As an added bonus, Matthew decided Carlisle was a bounder and gave him a resounding sock on the jaw. Then he knelt in the snow and asked Mary to marry him. Chap!

Fellowes ladled on some light relief too. There was a delightfully silly sub-plot about Thomas (Rob James-Collier, pictured above with Siobhan Finneran) concocting a plan to curry favour with the Earl by kidnapping his favourite labrador and then heroically finding the beast again, while Nigel Havers was invited to the Downton party apparently just to provide sport for Maggie Smith's Dowager Countess (pictured below). Havers played Lord Hepworth, an impoverished nobleman and womaniser trying to bag a wealthy wife. "Hepworth men don't go in for loneliness much," said the Dowager beadily.

How true. Not only was he trying to ensnare the Earl's sister Lady Rosamund (Samantha Bond), he was also knocking off her maid, Marigold (Sharon Small), and was caught in flagrante by a posse of Downton ladies. An absolute cad of the first water. "He's lucky not to be playing the violin in Leicester Square," snorted the Dowager. Now there's a thought for series three.

Speaking of which, this Christmas spectacular has cleared the decks for a reboot. With Mary to be married and Lady Sybil off in Ireland with the ex-chaffeur (prompting dark mutterings from the Earl about "Fenian grandchildren"), only Edith (Laura Carmichael) remains in search of a husband, preferably one in possession of a good fortune. Daisy (Sophie McShera) the daft scullery maid is benefiting from the firm guidance of Mr Mason (Paul Copley), father of her dead husband William, and feeling an urge to better her station in life. And Thomas, to the incredulity of Mr Carson the butler (Jim Carter), has successfully duped the Earl into believing that he is a kind, sincere person after all. Bags of ammunition for the nation's favourite aristo-soap. Oh, and nearly forgot - at the 11th hour, Mr Bates's death sentence was commuted to life imprisonment. You didn't think they'd really hang him, surely? It would have been worse than shooting the horse in Young James Herriot. 

Watch video of the Downton cast answering fans' questions in New York