John Hamm in the Black Mirror Christmas special.
It's Christmas - a time of peace on Earth and goodwill to all men - which also makes it a great time to watch something a little nasty.
The tradition of a good Christmas horror story dates back centuries. After all, half the cast of the greatest Christmas story of all - A Christmas Carol - are phantoms from beyond the veil. And there is still something charming in the contrast between Christmas cheer and something spooky, making it the perfect time for ghost stories.
Christmas has been used as a backdrop for plenty of horror movies, which usually consist of a maniac dressing up as Santa and going on an axe rampage, but the Christmas horror story is more restrained than that - nobody wants to deal with too much gore when they're digesting their steam pudding, but they can handle a little fright.
British television producers knew the value of a good Christmas night scare, and adaptions of the works of classic ghost story writers like M R James were a familiar fixture on Christmas television in the 1970s. Sights like the distant figure on the eerie beach in Whistle, And I'll Come To You, which kicked off that wave of Christmas adaptions, became just as traditional as crackers and paper hats.
MR James stories are still being effectively translated into good TV, with Mark Gatiss' adaption of the Tractate Middoth appearing last year, but the latest addition to this tradition is built on a pleasantly 21st century kind of horror: one of fears about media and technology taken to their extremes.
Black Mirror - created and written by acerbic British wit Charlie Brooker - is an anthology horror series with very modern concerns, as the darkest terrors emerge in the bright light of the modern media landscape.
After two seasons that saw a Prime Minister do beastly things with a pig, and horrific reality shows replace capital punishment, the series is back with the feature length Black Mirror: White Christmas, screening in New Zealand tonight on Sky's Soho Channel.
Watch the Black Mirror: White Christmas trailer here:
Like those terribly restrained classic adaptions on the 1970s, Black Mirror special isn't gory, but doesn't skip on the brutality - innocent lives are lost and the justice metered out can be just as savage. There is nothing supernatural in the three stories that make up White Christmas, just two men talking about how their lives were destroyed by unexpected side effects of near-future technology, but there is plenty of horror, especially when the actual reality of the situation is unveiled.
Black Mirror stories take the classic Twilight Zone angle where things, from the tiniest touches to the whole of reality, are very rarely what they seem, and where strange and terrible secrets are lurking beneath the surface.
Rafe Spall in Black Mirror: White Christmas
It's not all gloom - Brooker's dark sense of humour infuses the show, with a sense of utter nihilism sparking up against total satire. In tonight's special, this tone is backed up by a strong cast, with John Hamm using his Don Draper charm once again to do terrible things, while the ubiquitous Rafe Spall hides the nastiest secrets of all.
Some might say that Christmas night is not the best time for watching something so grim - that it is the time for family and love and goodwill - but watching some so dark during the happiest time of the year just makes the contrast between light and dark stuff even stronger, and can be a welcome antidote to the forced smiles of the season.
If Black Mirror isn't unsettling enough for your Christmas night, the internet is full of good scary stuff, and recent films from the US Cartoon Network's Adult Swim are some of the scariest. It's infomercial run of short films are 10 minute chunks of mind-bogglingly weird and esoteric horror, jumping out at the unsuspecting viewer at random times.
The series has already produced the viral 'Too Many Cooks' film, a meta-tastic take on TV sitcom credits that are invaded by a fourth-wall breaking psycho killer, but the more recent 'Unedited Footage Of A Bear' might just be the most genuinely disturbing piece of horror fiction in the past year, starting out as an annoying ad for anti-depression pills, and going off on an insane descent into psychosis, via violent doppelgangers and menacing phonecalls.
If you're over the saccharine sweetness of the festive season, it could be worth your while to take this 10-minute trip into darkness
• Black Mirror: White Christmas screens on the Soho Channel tonight at 8.30pm