Count Vassili Alexandrovich Obelensky is a Russian noble, highly religious and ardent monarchist and despotic aristocrat with vast estates in the Ukraine. For many years was an important advisor of Czars Alexander III and Nicholas II as well as an ambassador.
The Count is rather senile at first, with occasional seizures which Robert Cath treats with herbal medication.
During a confrontation with his granddaughter's lover Alexei Dolnikov who attempted to kill him with a bomb, the Count, in his delirium, stabs the young anarchist to death. Tatiana, wracked by guilt and shocked by Alexei's death, assumes an almost catatonic state.
Even during the Serbian hijacking attempt, they do not move from their table in the dining car. The Count displays a certain aspect of what might be called clairvoyance as he claims that those who were evacuated to the sleeping cars will never reach Constantinople.
In the end, as the train reaches its final destination, Tatiana opens the gun cache and blow them up with what seems to be Alexei's lighter.