In this era of lucky dip sequels, when you never know which Roman numeral after a title is going to be a mark of quality, it is nice to see a film series that doesn't just adhere to the old-fashioned rules of diminishing returns but makes it an artistic statement.

Before Sunrise, in which the early twentysomethings Jesse (Ethan Hawke) and Celine (Julie Delpy) meet on a train and spend a romantic night walking around Vienna before going their separate ways, is superior to Before Sunset, where they meet up again nearly a decade later to walk around in Paris and rekindle their love, which is better than this latest one where they are a couple in their early forties walking around Greece during a summer holiday. Regardless of the films' individual qualities as they move away from the spontaneity of youth and romance towards the responsibilities of middle age, they must, inevitably, become less vital.

That said, I suspect Midnight is a slightly weaker film. Since it isn't set in a major European city, it doesn't have that sense of place the others had. These long twisty conversations just seem to be happening in front of standard tourist scenery and, apart from the monologue by Natalia (Xenia Kalogeropoulou) about her dead husband, they aren't as engaging as in the previous films.

Jesse and Celine have always been loose constructions, the thinnest veneer to cover Hawke and Delpy playing versions of themselves, but this time the gap between character and performer seems thinner than ever and the film somehow smugger.

Also, you sense that the film favours him over her and agrees with Hawke's estimation of himself as basically a good guy, while Delpy comes across as a bit of a shrew in places.

Part of you has to wish they'd left it with the first film – the lovely ending that skipped back through all the places in Vienna they'd spent the previous evening, now in daylight, nothing special but in their memories places of magical significance – and an undercurrent of Midnight is their own mixed feelings that they couldn't just leave it at that.

It's too late now; I imagine we'll be seeing them once a decade until one of them dies. At some point in each film there is the revelation (and it always comes as a surprise) that while I don't really like these two people, I am enormously wrapped up in their fates. Anyone who was taken with Before Sunrise now has a lot riding on this couple and how each of these films turns out.

BEFORE MIDNIGHT (15)

Director: Richard Linklater

Starring: Ethan Hawke, Julie Delpy, Walter Lassally, Seamus Davey-Fitzpatrick and Xenia Kalogeropoulou

Length: 108 mins

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