John Hurt, the star of The Oxford Murders, recalled at its premiere in the city last week that he had last filmed here nearly 30 years ago on Michael Cimino's Heaven's Gate. The vast sums lavished on this legendarily over-budget movie contrast sharply with the parsimony evidently practised over the new and rather disappointing film from Spanish director Álex de la Iglesia. Cimino spent weeks transforming Mansfield College into 1870s Harvard - thousands of leaves were stuck on trees to give the appearance of high summer - for a scene that lasted two minutes; de la Inglesia spent less than a week in Oxford (and infinitely tinier sums) on the making of a whole film.

This is because The Oxford Murders was principally filmed in London, with familiar landmarks in the university city introduced in the main as scene-setting 'dressing' shots. For much of the 110 minutes of the film I was struggling to identify the locations of the action, before discovering as the credits rolled that we had not really been in Oxford at all. True, the cinema audience pays a brief visit to a concert at the Sheldonian Theatre (was that someone daring to occupy the Chancellor's Chair?), before crossing the road for a much longer meander through the miles of shelving in the Norrington Room of Blackwell's bookshop. But those in search of the spirit of Oxford had better buy themselves a set of Morse DVDs.

They would certainly be able to enjoy a more sensible and intelligible plot than is offered by this quasi-academic hokum. Despite the fact that I had already read the (rather good) novel on which it is based, by the Argentinian writer and mathematician Guillermo Martínez, I found myself puzzled by various twists in the story and its unlikely denouement.

Perhaps this was the intention of its makers, with a puzzle so firmly placed at the centre of the plot. It concerns a young Argentinian mathematics graduate (Elijah Wood) who arrives in Oxford to continue his studies with one of the country's leading lights in logic (John Hurt). Alas, both quickly find themselves sidetracked by the murder of Wood's elderly landlady, which its perpetrator advertises as "the first of a series". Working out where this series will lead is the challenge to the intellectual resources of this unlikely pair of sleuths. Meanwhile, the rest of us will be wishing we possessed the little grey cells necessary to keep pace with them.

While Hurt - looking all of his 68 years - gives the impression of barely keeping a straight face during the delivery of some of his silliest lines, Wood at least brings a certain earnest seriousness to his acting. The eyes certainly have it where this actor is concerned, sticking out bold, blue and wide as those of a frightened lemur. Admirers of the 27-year-old American star will perhaps be interested to know that he has his first screen sex scene here. His performance with a pneumatic nurse played by Leonor Watling reveals rather more of his physique than he displays as Frojo in Lord of the Rings. Since he will soon be playing the legendary rock lothario Iggy Pop on screen, he needs all the practice in this area that he can get.