After their highly successful collaboration five years ago on the film Iris, the director Richard Eyre and Dame Judi Dench have teamed up again to create the story of another writer — of sorts — suffering from delusions. Her name is Barbara Covett (Dench), a lonely schoolteacher whose only companion is a cat and whose only confidante is her diary. In Iris, Dench played a woman suffering from a disease (Alzheimer’s); here, she plays a woman who is the disease that others suffer from.

The most surprising thing about Eyre’s film of Zoë Heller’s fine novel is that, when you leave the cinema, you have nothing to talk about. Reader, be prepared: once you have pointed out that Dench gave a terrific performance, that Cate Blanchett looked stunning and that Bill Nighy was great, there’s nothing left to say. Yes, Notes on a Scandal is that shallow.

The scandal in question is the love affair between the beautiful Sheba Hart (Blanchett), a married woman who teaches art at a London comprehensive, and one of her pupils, 15-year-old Steven (Andrew Simpson). The notes are kept by Sheba’s colleague Barbara (Dench), a spinster who believes that she has found a new best friend. When she discovers Sheba and her pupil lover at it, she turns the screws on Sheba.

Notes on a Scandal badly wants to be the thinking person’s Fatal Attraction. There are no boiled bunnies here; instead, we see Shebagetting a salacious grilling at the hands of the tabloid press. But it has none of the vulgar energy and tension of the earlier film. The trouble with Patrick Marber’s screen adaptation is that it’s hard either to care about the downfall of Sheba or to fear having a Barbara come barging into your life.

Notes on a Scandal fails to bring the affair between teacher and pupil alive, or make it seem true to life. (And, by the way, beautiful bohemian women like Sheba don’t sleep with 15-year-old schoolboys; they sleep with fat middle-aged men who are bigwigs at the BBC, or famous poets.) Beneath all the subtle observations about class, this is really just the familiar tale of the middle-aged man with a midlife crisis who sleeps with a young girl — only this time around, it’s a woman. We’re meant to pity Sheba not because she has lost her moral bearings, but because she has behaved in a way that means she has lost her big house and nice husband (Nighy).

I’ve been trying to figure out what this film is really about, and though Marber has said that in Barbara, we see a product of a certain kind of “modern loneliness”, I think it’s about Eyre’s fascination with Dench. It’s a film that says, look at this terrific performance! And that’s what’s wrong with it — we get an unforgettable portrait of a lovesick monster, but one stuck in a rather ordinary film.

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