How could Lord Grantham have allowed Tom Branson into the family? He was always a triple threat: he's working-class, he has views and worst of all, he's Irish. Last week he was sitting at the dinner table calmly passing the port and inviting Matthew to play billiards like a normal, posh person: a dreadful subterfuge. Lord G should have shot him there and then.

This week's top crisis was heralded by Tom banging on the door late on a wet night, halfway through dinner with the Archbishop of York. This was already a fraught occasion, with Carson having whined about still being short-staffed and Lord G replying that they would, upon the visit of the region's top man of God, "fudge it".

Now, though, the problem of the cigar box being opened three seconds later than is proper faded away, as Tom announced that he'd left Sybil in Ireland because they were both on the run from the Garda. Tom hadn't done anything wrong: yes, he was there when some British toffs were run out of their house and it was burnt down, and yes, he'd been to all the planning meetings, but when it happened he felt bad. He was basically totally innocent.

Lord G and the Crawleys feared, however, that the law might not agree, so off he went on the overnight crisis train to knobble the Home Secretary.

Anna Bates and her husband, Bates Bates, were upset when they both found that letters from the other had dried up, but neither knew why, making them fear they'd gone from the sickliest couple of the between-war era to a divorce, overnight. Bates also didn't know why Anna hadn't visited. Anna did, but didn't connect this with the lack of letters, the shortage of housemaids at Downton having left her too busy to analyse holes in the plot.

Over a bowl of gruel, Bates got wind of a plot against him. It turned out his cellmate was the Harry Grout of the nick – the last guy you want to angrily piledrive into your cell wall. The conspiracy against Bates went right to the top. What their revenge would be was TBC, but it would be the terrors of the earth.

Bates would have to be on his mettle like never before. Then it happened: the screws came in just like last week and turned over the beds, hunting for illicit snuff that looks like bits of old carpet. Was Bates doomed? No! He'd found the incriminating bundle and moved it into the other guy's bedding, so he got carted off instead, Bates and Anna's letters were released by the crooked prison officers and now everything's more or less fine.

Meanwhile, there was tingling downstairs as a stunning blonde arrived to interview for the vacant first footman position. The maids stood still and giggled, while even Mrs Hughes did a double-take. Carson wasn't overly impressed with the dreamboat, but was told by Lady Mary to hire him for the sake of everyone's morale.

Carson prefers Alfred, the gangling man-child. They shared a touching quasi-paternal moment as Alfred was given the grand Downton spoon quiz: the six spoons of Downton, laid out in a row to be named. Alfred scored a healthy five out of six, naming the tea, egg, melon, grapefruit and jam spoons, but failing on the boullion. Remind me not to stop off for chips on the way if I ever get an invite to dinner at Downton.

Thomas hates Alfred, so he saw the new guy – Jimmy, soon primly rechristened James by Carson - as someone who needed befriending, especially after he caught Mr Below-Stairs Sex in his room, half-dressed. Thomas is gay again! Hooray! Lady-lovers also got a new lust object as a pretty new kitchen maid called Ivy arrived, just as Daisy was about to ask Alfred out for half a mild and a cupful of chip scrapings. Alfred instantly started perving over the new girl, sending Daisy back to her natural habitat: furious, downtrodden despair.

Lord G arrived back from London with news that Tom was in the clear so long as he never, ever went back to Ireland – Tom expressed gratitude but the big man is wise to him now. His suspicions were right: Tom seems determined to return and fight against the British yoke, even if this means giving up the romantic jackpot that is marriage to Lady Sybil, not to mention her unborn child.

An upsetting sub-plot saw Ethel give up her son to his late father's sniffy parents, having concluded that her life as a prostitute could do the lad no good. After a lot of scenes where the boy's grandad and even Mrs Bird the cook were really quite openly prejudiced against sex workers, Ethel refused an offer of help with her upkeep and sent her son away. Isobel Crawley remained resolute but it looked pretty final: Mrs Hughes remarked that in those days, once you were down, you were out.

Lady Edith might have been jilted at the altar, but she's in a position to fight back, unlike Ethel. A lonely breakfast with just her dad and Matthew – rather wonderfully, it turns out that women at Downton get breakfast in bed, but only if they're married – prompted her to write to The Times about the struggle for voting equality.

"It won't be published," said Lord G, but it was – not only that, but the paper was so pleased it ran it as a news story as well as on the letters page, a bit like when a bishop writes to the Telegraph now. Lord G had only just been scraped off the ceiling after the Branson business – he shot back up there. By the sideboard, Carson honked discreetly but furiously.

And still that's not the greatest cloud hanging over Downton. Matthew, as the new co-owner, has been going through the books and has found that Downton is a cross between Enron and Trotters Independent Traders. Can he get his Lordship to listen?

>> Series three, episode three: Carson turns detective, O'Brien goes to war

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