"The trouble with you lot is, you're all in love with the wrong people!" Since she had her cataracts done, Mrs Patmore sees everything. This week lust once again coursed through the kitchen in a way that, under a less attentive head cook, could have led to singed parsnips and spoilt rice pudding.

Ivy continued to attract Alfred's sledgehammer flirting. The gangling man-child pressed on despite the looming, sarcastic presence of caramel-haired dreambucket Jimmy, sniping suavely from doorways, and Daisy angrily barking at Ivy to get on with her mashing and whisking.

By the end of the episode, Alfred had conned Daisy into teaching him the foxtrot, leading her on that this meant erotic frissons were back on between them, when in fact Alfred was using her as a warm-up for Ivy. Jimmy interrupted, explained this, and danced a superior foxtrot with Daisy to boot – a double victory that was wiped out completely when Carson walked in, exploded, and confirmed that Alfred is his preferred footman. Alfred might be alone but it looks like he's on for an extra thruppence ha'penny a year.

Daisy probably isn't that bothered about the romantic snubs, as she's been given a ticket out: Egg's dad from This Life wants her to run, and indeed inherit, his farm, with its potential for lucrative jam and chutney sales. A nice moment showed us that Mrs Patmore, faced with the loss of her surrogate daughter, very much is bothered about this.

That left Thomas's efforts to snare Jimmy, which were even less subtle than Alfred cracking on to Ivy. When Jimmy tried to cheer everyone up after the whole sudden death of Lady Sybil thing by jamming out some smokin' ragtime boogie-woogie on the kitchen piano, Thomas was straight over, chummily grabbing his shoulder before even more chummily – bizarrely, in fact – fondling his neck in full view. Jimmy confided in O'Brien that he's not down with that. She retired to the linen closet to brood on how to destroy Thomas with this intel.

Bates's bid for freedom looked to have stalled when the Crawleys' lawyer, Murray, called on the shifty washerwoman, only to find that she'd been knobbled and was recanting her baffling but crucial story about a pie. Bates himself was goaded about this in the exercise yard by the incredibly crooked screw, whose hat is now so far down over his eyes, the peak has become a beak.

When Anna and Murray visited Bates with the bad news, he promised to do something about it himself, despite being in prison. "Nothing foolish!" pleaded Anna, perhaps sensing that her husband's likely course of action wasn't a letter to the Times, or a devastating series of put-downs over coffee and petits-fours with the prison governor. Sure enough, next time Bates was trotting round in a tight circle, he grabbed his old cellmate and threatened to shop him for drug-dealing, while pointing out that making a washerwoman perjure herself could have consequences. As well as the verbals, Bates was brandishing a sharp bit of metal, which he pressed several inches into one of the villain's chins.

This belt, braces and elasticated waistband approach to putting on the frighteners seems to have worked: by the end of the episode, Anna was seen sprinting across the lawn away from the house, towards where the "See The Real Downton" coaches are parked, to intercept Mary and Edith with the news that Murray was confident the conviction was unsafe. So that's all fine now.

Isobel Crawley reacted to the aftermath of Sybil's passing in the only way she knows how: jolly well inviting Cora, Edith and Mary (and the Dowager Countess, who was hiding behind a high-backed sofa when Isobel made the offer) to a lunch party. The problem: as she conjured the plan, she was spitting out Ethel's latest bowl of curdled soup. Isobel urged Ethel to just get some ham in, but her new cook was determined to use this, of all occasions, as a training ground.

Ethel approached Mrs Patmore, who snuck into Crawley House with some recipes and a lot of brusque encouragement. Carson, who thought he'd made his views on ex-prostitutes quite clear last week, clocked Mrs Pat sneaking out and tried to dress her down back at the Abbey, only to find himself undermined by Mrs Hughes, who stayed firm throughout the episode despite Carson's eyebrows disappearing up into his hair. Touchingly, they concluded by reaffirming their platonic devotion, despite each thinking the other has lost it vis-a-vis lunching with loose women.

Ideological debates were raging upstairs too, as Tom announced over breakfast that his baby daughter, whom he bravely wants to name Sybil, would be raised as a Catholic. Lord G was about to have a sip of tea but the cup went straight down again and may never, I am sorry to report, have been drunk. Later, at dinner, Tom repeated his wish, despite Carson standing nearby wielding a lethal-looking decanter full of sherry, and despite the presence of creepy local clergyman, Rev Travis.

Travis always looks as if he's come straight from a hard day eating children and burning witches at the stake, but he really overstepped the mark here by telling Tom that God loves Anglicans more than Catholics. This argument fell to pieces when Tom, Matthew, Edith and Mary piled in to ask whether God hates the French, the Italians, the Portuguese, the Spanish, South America and, widening the debate to any non-Anglicans, the whole Indian "sub-continent". Travis was holding his own when it was just the French and Italians God might hate, but he faltered after that. Mary killed him off by deciding now was the time to drop the bombshell that Sybil Snr's dying wish was to let the baby be, in Lord G's phrase, "a left-footer".

The undercurrent to this was Cora's continuing fury that Lord G might have stopped Sybil being saved, leading her not only to keep him out of the marital bed but to attack him for his old-fashioned attitudes. Her disloyalty was the only thing souring proceedings as the Downton ladies lunched at Isobel's – she urged Edith to ignore her dad and write her newspaper column, but the shock of this was cushioned by Ethel's food. Under Mrs Patmore's tutelage, she'd triumphed.

Lord G ruined the day, however, bursting in to reveal that Ethel is or was a fallen woman. Already livid about the baby Sybil debate, and about Matthew finally broaching the fact that Downton is run about as efficiently as a week one Apprentice task, his Lordship angrily demanded that everyone come straight home.

Cora stood her ground. Blaming Lord G for his daughter's death was one thing, but openly and knowingly chowing down on a prostitute's salmon mousse? Surely their marriage was over!

The Dowager Countess already had a plan in train. She'd spoken to Clarkson, the reassuringly Scottish doctor, and now he told Lord and Lady Grantham that Sybil wouldn't have survived even if Lord G had sent her off for surgery. Clarkson slightly gave away that this was a kind pack of lies by glancing at the DC throughout, but it seemed to do the trick: his Lordship has his wife back, if nothing else.

>> Series three, episode five: Anna cracks the case, Lady Sybil gives birth

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