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In December 1927, a funeral car arrived in Leningrad, at the Moscow railway station. It brought an urn with the ashes of academician Vladimir Bekhterev and a glass jar with the brain of a scientist hidden from the public eye. Just a few days before, he had gone to Moscow for a congress of psychiatrists. However, according to a telegram recently found in the archives of the Leningrad Institute of the Brain, Professor Bekhterev was urgently summoned to Moscow by the Council of People's Commissars. The last time he was summoned to the Kremlin was three years earlier to see the seriously ill Lenin. To whom was this urgent call? What happened on that mysterious night before Christmas? And are there any documents about the illness and death of Academician Bekhterev?