She's such a great interviewer that this chat with Kenneth Branagh feels like it deserves an entire series. It's relentlessly charming - and hugely moving when they talk about Dame Judi's late husband.
Cast your mind back to Christmas 2017, and you might remember a slightly wacky BBC documentary called Dame Judi Dench: My Passion for Trees. On the surface, it seemed like one of those god-awful shows put together by tombola; matching a celebrity with a random subject and hoping it would pass muster.
However, this was not the case. Dame Judi Dench, it turned out, really did have a passion for trees. An obsessive passion, one that manifested itself in a small woodland where she named trees after friends of hers who had died. The result was unexpectedly tender and gorgeous, and the show ended up being the best thing on TV that Christmas.
So it's easy to see Tea With Judi Dench as a sequel of sorts. Like the tree show, there isn't much on the surface to get excited about. It's a show where someone comes to visit Dench for a cup of tea and that's literally it. Which would be dispiriting - another brilliant career lost to podcasts - were it not for the punishing, relentless charm of the thing.
Dench's guest for the episode is Sir Kenneth Branagh, and the two of them go way back: by her own calculations, Dench has played Branagh's wife, mother and grandmother in her time, and the pair share a lovely, easy, breezy relationship. Branagh pulls up outside her house, Dench barks, "About bloody time!" and then presents Branagh with a huge portrait of his own head. It is to his eternal credit that Branagh doesn't immediately freak out and run away.
This sets the tone for the rest of the show, in which they natter away pleasantly with no real direction. They eat some potato farls. They pretend not to have read any of their reviews, even though Branagh is able to quote them extensively. At one point they potter over to Sweetheart, Dench's parrot, in the hope that it will call Branagh a "slag".
Mainly, though, they reminisce. They talk about all the times when Branagh directed Dench ("Was it headscarf acting?" she asks, self-deprecatingly, of her role in his Hamlet adaptation) and of the time that Dench directed him (it's glossed over very quickly, but it's implied that Branagh got in a huff and walked out when Dench tried to give him notes). They talk about people they've known and lost. They quote Shakespeare to each other, at length.
Which, again, doesn't sound particularly appealing, because nobody in their right mind would want to spend Christmas listening to a pair of old luvvies tell each other how brilliant they are. Nevertheless, it turns out that, in her own way, Dench is actually a pretty nimble interviewer.
The closest comparison I can think of is Drew Barrymore. Dench spends much of her time with Branagh sitting extremely close to him, leaning in, eyes wide open. She nods along with his stories, hanging on his every word. She is an extraordinarily intent listener, drawing out details that Branagh might not give up during a conventional interview.
This isn't a great approach for all interviews, because it tends to encourage the subject to go long, soaking up the allotted time with indulgent waffle. But for this - an edited show about two old friends with clear affection for one another - it's perfectly pitched.
Tea With Judi Dench is billed as a one-off. In an ideal world it would be a series, because surely there's no end of actors who have worked with Dench and would love nothing more than to discuss their shared history while being insulted by her parrot. Whether that will happen is anyone's guess.
This is partly due to age. Dench - while resolutely pin-sharp and mobile - just celebrated her 91st birthday, so the idea of committing to a full series of interviews might not hold too much appeal. But also, Branagh is such a spirited interviewee that the magic of their encounter might not be easily replicated.
The section on Dench's late husband, Michael Williams, in particular, is the highlight here. Her house is full of trinkets of the pair of them, and when Branagh pulls out a tablet to show her a clip of Williams in Henry V, she's moved to silence by the sight of him. If there's a lovelier, more touching moment on television this month, I'll be staggered. Judi Dench has run away with Christmas once again.