SIR - The organised letter-writing campaign mounted by some members of the Polish community against the film of my novel Enigma has surprised me. My book was published in 1995, and was translated into Polish in 1996. Of approximately 1,000 letters I have received from readers since, only one has ever complained of its depiction of the Poles.

The latest attack on my supposed "error", Jozef Garlinski's letter (Oct. 3), is itself full of errors. I did not base my novel on his book Intercept. My novel does not suggest that "everyone" at Bletchley Park knew of the existence of the Enigma machine: rather the contrary. Nowhere do I claim that Ultra was"the name of the code-breaking uni": every schoolboy knows that Ultra was the code name given to the fruits of signals intelligence (and not, pace Mr Garlinski, to the worldwide network that produced it).

I was well aware when I wrote the novel that no Pole worked at Bletchley Park, which is why the character who has caused so much indignation holds a British passport, and is the son of an English mother and a Polish father.

His (fictional) situation was inspired by a real-life character who also had a foreign aspect to his background: Walter Ettinghausen, a German-born Jew who worked in the Naval Section and who, in 1943, translated a decoded intercept referring to the Final Solution.

In the novel, as in the film, my fictional Polish character also discovers the existence of a great crime in 1943, and it is this that motivates him. Far from seeking to be gratuitously offensive about the Polish contribution to the breaking of Enigma, it was partly my anger at British disregard for Polish suffering that fuelled the novel. For six years, the vast majority of readers of Enigma have clearly recognised this, and I hope that cinema-goers who approach the film with an open mind will recognise it, too.

Robert Harris

Kintbury, Berks

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