In pure terms of timeline it has been said that America tends to be ahead of the UK when it comes to new movies, TV shows or video games. True.

29 downton blog Downton Abbey grips America in the nostalgia of the past

But in one crucial area this country is precisely three months behind Great Britain. So please forgive me for sounding, well, so yesterday. But since Sunday night I – and about 15 million others living in the USA with access to public television – have been soldiering through the many stages of grief.

The Twittersphere has been draped in black and even the august Washington Post has been by our side. Like a family doctor explaining a terrible tragedy, its online edition has a front page medical expose of eclampsia, the pregnancy condition that killed Lady Sybil, the youngest and prettiest of the Downton daughters on Sunday night at 9.48pm.

Patiently and forensically the article spells out which women are at risk, what the warning signs are and how the fatal seizures might have been avoided by doctors in Britain in the 1920s. These are all the questions that I was screaming at my TV screen on Sunday night, much like the Granthams who had to watch Sybil die while one physician, with a knighthood, stood there in his silk dressing gown muttering something about the whims of nature while the other - the local family doctor who has no knighthood but knows his eclampsia – was mouthing “I told you so”.

The brutal truth is that Lady Sybil was killed by the British class system. If His Lordship, Sybil’s father, had not shown excessive deference to a doctor with a knighthood, who had spent a career delivering royal babies and who was blithely indifferent to the symptoms of pre-eclampsia, then Sybil might still be with us. I can only console myself with one thought: what really killed Sybil was a film offer from Hollywood that meant she couldn’t continue working on Downton Abbey’s next season and had to be written out of the script. Julian Fellows you are a cruel fellow.

Enough already, I hear you say. Haven’t you got better things to blog about like the debt ceiling, immigration reform or gun control? Indeed. But Downton Abbey has become an American phenomenon. It clocks up the kind of viewing numbers that haven’t been seen on public TV since Upstairs Downstairs captivated America in the late 70s. There are dinner parties organized around Sunday night viewing sessions.

PBS, the public TV channel, whose schedule tends to be more like a well worn perforated sofa, is planning a jewelry line. At awards ceremonies the cameras find Lady Mary as much as they do Beyonce or Amy Adams. And when Downton Abbey’s latest series was launched after Christmas the cast went on a road trip through America. They were feted like royalty. The British embassy gave them a special reception.

In reassuring tones, Carson guided a fascinated but befuddled public through the hierarchical minefield of valets, footmen and butlers on the American morning shows. The anchors nodded in deference. Snobbery, it turns out, is still one of our best exports. America, a society supposedly based on classless meritocracy, is of course obsessed with the class system - its own - precisely because it is a vice that in this country dares not speak its name. It has always been much safer and more entertaining to leave the pornography of class to the Brits as long as it is brazen and nostalgic enough.

Impossible hats, gorgeous stately homes and steaming tureens of turtle soup are de rigeur. And all that decorum only works if it conceals a cauldron of sex, intrigue and death. Downton Abbey – like our own dear royal family - delivers all the above in spades but unfolds the action with the breathlessness of 24 or Homeland.

This may explain my recent encounter in one of the roughest neighborhoods of Baltimore – the city that brought you the polar TV opposite to Downton Abbey, the Wire. Two men in hoodies – one built like a wardrobe, the other, tall and skinny – emerged out of the twilight of a derelict house. My cameraman, Dai - also a hopeless DA fan – and I were filming for a piece about the state of the economy.

We had been warned about this area. It was getting dark. We were alone. The men approached fast. The big guy had his hand in his pocket. “YO!” he shouted, “where you from? What you doing?” In the politest British vowels, we explained that we were filming a piece about Baltimore for Channel 4 in the UK. “UK, you mean, like, Britain?” the skinny one asked. Indeed.

“So what I wanna know,” the skinny guy said. “When exactly is the third series of Downton Abbey coming on PBS?” It was November. We only had another two months to wait and Sybil was still alive.

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