But Richard Eyre's unsentimental and absorbing film joins Last Orders as a British work rejoicing in the strengths of our film industry and bringing out the best in a rich array of talent.

Judi Dench and Jim Broadbent join up to play Iris and her beloved husband John Bayley as she battles against the mentally debilitating disease as he can only look helplessly on.

The eccentric couple lived a life firmly in the world of Oxford academe - book-strewn houses, college dinners, carefree pushbike rides and intellects the size of a planet.

Iris was the bright light of her generation - frequently described as "the most brilliant woman in Britain" - she dazzled her contemporaries and also enjoyed a rich social life.

Bayley (played in his younger days by Hugh Bonneville) watched from the wings a stuttering young fogey but slowly his interest and empathy won her to him.

The young Iris (played beguilingly by Kate Winslet) was the dominant party but as the disease began to take over it was John who had to be strong.

First it was little things an inability to spell a simple world and then as Iris disappeared into its clutches - in a moment of sheer anguish - the philosopher novelist is reduced to singing along with the Teletubbies.

The delicate slide is handled with care and there are enough moments of low-key humour to leaven the deadening hand of the mind-numbing disease.

At the end of the day, this is a simple love story albeit featuring one of literature's most celebrated couples.

Dench plays the increasingly confused Iris without a hint of self-pity while Broadbent turns in a bravura performance as the loyal husband standing by her side.

This is a dignified, unsensational story exquisitely told and subtly acted and deserves a wider audience than the subject matter would expect.

Tim Evans