Ammonite: Even the Saoirse Ronan-Kate Winslet sex scenes are too respectable

A year or so ago, when Francis Lee, director of the excellent God's Own Country (in which a new arrival to a rainy part of England had a passionate same-sex relationship with Gemma Jones' grumpy offspring), announced that his next project (in which a new arrival to a rainy part of England has a passionate same-sex relationship with Gemma Jones' grumpy offspring) was to hang around Mary Anning and Charlotte Murchison, two admired 19th-century fossil-hunters, at least one relative of the former raised polite objections. There is no evidence whatsoever that the two were romantically entangled.

Who really cares? Since the time of Sir Walter Scott – and long before that – creators of historical entertainments have been tweaking and poking what we naively call "the facts". It is true that the film-makers in this instance have also reversed the age difference. In real life, Murchison, played here by 26-year-old Saoirse Ronan, was a decade older than Anning, who is given grim presence by 45-year-old Kate Winslet, but it's not as if Cleopatra looked much like Elizabeth Taylor.

And yet. Seeing the finished film, one finds oneself wondering if the modern-day Anning family members might have had a point, though there is plenty to savour. Lee has as sound a grasp of rain-blasted Lyme Regis as he did of mud-splattered Yorkshire in God's Own Country. Stéphane Fontaine's cinematography works hard at bleeding washed-out shades through a location where even the food – mushrooms, the most grey of all foods, for luncheon – tends towards pathetically fallacious monochrome. Nobody could fault Winslet or Ronan for effort. Fiona Shaw is here to offer stalwart support as an older mentor.

But whither the palaeontology? When it comes to what we learn about Anning and Murchison’s achievements, the film may as well be set among shelf-stackers in a suburban hardware giant.

Is some sort of analogy at work? The film introduces Anning as a determinedly committed grump prowling the beach in search of the ammonite fossils she and her cat’s-bum-mouthed mother (Jones, always excellent) will sell in their shop. Anning is then shaken out of everyday habits when a visiting geographer (James McArdle) introduces her to his “melancholic” wife (Ronan in hyper-curls) and the two women move from one sort of bonding to another.

If you were prepared to put in the work, you could read the fossils as representing Anning's presumed sexual repression: calcified, submerged, left unattended. But does digging the things up work as a metaphor for release? They are still fossils. Jurassic Park makes more sense as an analogy for liberated sensuality (but don't quote me on that).

Acting showcase

Anyway, we still have a chance to watch two of the era’s greatest actors at work. Winslet fares better with meatier material. Her face scrubbed with the make-up that looks like no make-up, head powering forward, voice permanently clipped, she gives us a convincing take on a woman who has embraced voluntary tunnel vision – look left or right and she may be reminded of unfulfilled desires.

Ronan, as always, does the best she can, but this is a thinly written part that gives too few clues as to motivation. Her dialogue feels like initial sketches for a character rather than a completed draft. There is no smidgeon of the complex dynamics that drove Céline Sciamma’s superior, structurally similar Portrait of a Lady on Fire.

Much attention has inevitably been focused on the explicit sex scenes between the two leads. It may be unkind to constantly harp back to Lee’s previous film, but, though coyness is as absent as gratuitousness, we get little of the messy, squelchy chaos that made the al fresco coupling so convincing in God’s Own Country. The scenes feel meticulously planned. They should, of course, be planned, but it would be better if they looked as if they weren’t.

We are left with a perfectly respectable, eminently professional slice of prestige arthouse. Nobody with even modestly open-minded sensibilities will walk away in a blind fury. Few will leave in an ecstasy of transcendence. It already feels as if this supposed awards magnet never existed.

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