Mothering Sunday is ostensibly a story of a 1920s affair between a housemaid and a friend of her employer. But there's a lot more to it, says Simon Morris.
Simon Morris: The setup and the supporting cast of Mothering Sunday imply we're about to see something we're used to...
The young maid-servant - Odessa Young - sneaking off to have a fling with the local squire, played by The Crown's Josh O'Connor is straight out of Downton, you'd think.
Jane works for his neighbours the Nivens, played by Colin Firth and Olivia Colman.
But Mothering Sunday has rather more on its mind than sentimental nostalgia. Jane has been in service since she was 14 but she doesn't intend to stay where society has placed her.
She's not sure yet where she's heading, but it's something to do with books and writing.
The main story of Mothering Sunday takes place on one day - the third Sunday before Easter 1924 - when Paul and Jane have arranged to spend their last day together. He's shortly to be married to the more socially acceptable Emma.
We cut between Jane and Paul's love-nest, and the family picnic in honour of the engaged couple. And we wonder at the undercurrent of sorrow, as the couple's parents and their friends celebrate the betrothal of Emma with the somewhat delayed Paul.
Why are there no other younger people there?
The reason, of course, is that nearly all their children - everyone except Paul and Emma, in fact - were killed in the War.
Even the Nivens, who have no direct connection with the upcoming wedding, were invited as honorary co-parents because their own son James is dead.
But there's more to the story than simply the irony of the love between the unsuitable couple - Paul and Jane the housemaid - contrasting with the dutiful arrangement between Paul and Emma.
They seem to be doing it as much for their parents and their friends as for themselves.
But the film's literary origins - it was originally a novella by Booker Prize-winner Graham Swift - tend to show as the action incessantly darts backwards and forwards, away from the actual events of one day.
A blink and we're in the village the day Jane started work at the Nivens, and first met the dashing Paul outside a shop. Another blink and suddenly it's years later when the older Jane is starting to write seriously, encouraged by an unexpected new husband called Gordon.
Then we flashback to when she and Gordon met.
This is not what audiences for a star-crossed lovers story, set in the comfy, class-conscious world of Julian Fellowes, are expecting. The presence of the reliable Colin Firth and Olivia Colman certainly reinforces that assumption.
But that's not what Mothering Sunday is out to do, or at least not just that. It's mostly a story about writing, about story-telling.
When the film flashes even further forward - good heavens, there's Glenda Jackson, back after 30 years in politics!- we belatedly realise the film's true purpose.
But despite the best efforts of a talented team of screenwriter Alice Birch and director, Frenchwoman Eva Husson, turning a good book into a coherent film proves challenging.
That said, Mothering Sundayy is one of those films that improve in your memory. The more I think of it now, the more impressed I am by it.
But at the time, I was confused by what seemed an overly-complicated timeline - where are we now? - when all I wanted was to be told the story.
In a book, of course, that's not a problem. When you get lost, you can always riffle back a few pages to get your bearings. But a film requires you to keep up, first out the gate.
I suspect that Mothering Sunday- like so many ultimately satisfying films - will improve on watching a second time. Possibly on Mothering Sunday next year.
