Fairness demands that I record, with slack-jawed amazement, the near-universal acclaim this film has received from English critics; honesty requires me to say I loathed almost every frame.
The week-end of the title (so punctuated because it's French) is a 30th-wedding anniversary trip to Paris undertaken by Birmingham couple Nick (Broadbent) and Meg (Duncan). He's booked them in to the hotel they spent their honeymoon at but she objects, on arrival, to the beige colour scheme and they wander the streets before booking into the presidential suite at a five-star joint.
Yes, she is demanding. She's also brittle, flaky, bristly, impetuous, neurotic, self-pitying and whiny. She is also, when push comes to shove, incomprehensibly cruel to Nick, who, to make matters worse, seems to lap it up.
It gives nothing away to say that Nick and Meg are at a crossroads: he's been discreetly sacked from his job at a second-rate university for making what we will later learn was a patronising, sexist and racist remark (though we're invited to chortle, "This is political correctness gone mad"); she wants to pack in teaching to "learn Italian [and] dance tango". Their sexless, joyless marriage is heading for the rocks.
So they spend their time in Paris feeling sorry for themselves, breaking the monotony by doing a runner from an expensive restaurant and running up a hotel bill they know they can't afford (behaviour that we are also implicitly asked to applaud).