The date was advanced several days when the terrorists learned that the Tsar was planning to leave for his summer palace in the Crimea. Assassins were planted in the square before St Isaac's Cathedral. But the Tsar did not appear and at twilight the conspirators returned to their underground headquarters. Ulyanov then heard that on 28 February the Tsar was to drive along the Nevsky Prospect, probably to attend memorial services at his father's crypt in the Cathedral of St Peter and St Paul. Once more the terrorists waited, but no Tsar's carriage appeared. The secret police, suspecting an assassination plot, had warned the monarch to remain in the Winter Palace.

Hours later the terrorists left their stations along the Nevsky and met in a tavern. One of them, Andreiushkin, had been shadowed for days by detectives. They followed him to the tavern, where he and his comrades were seized.
Ulyanov and his lieutenant, Lukashevich, after waiting impatiently all day, proceeded to their headquarters. The police were there to meet them. In Ulyanov's possession they found a code-book with a number of incriminating names and addresses, including those of the Polish revolutionary leaders Josef and Bronislaw Pilsudski.

Terror.... is the only form of defence by which a minority strong only in its spiritual strength and the consciousness of its righteousness can combat the physical power of the majority... Among the Russian people there will always be found many people who are so devoted to their ideas and who feel so bitterly the unhappiness of their country that it will not be a sacrifice for them to offer their lives...

My purpose was to aid in the liberation of the unhappy Russian people. Under a system which permits no freedom of expression and crushes every attempt to work for their welfare and enlightenment by legal means, the only instrument that remains is terror. We cannot fight this regime in open battle, because it is too firmly entrenched and commands enormous powers of repression. Therefore, any individual sensitive to injustice must resort to terror. Terror is our answer to the violence of the state. It is the only way to force a despotic regime to grant political freedom to the people.... There is no death more honourable than death for the common good.

There were five of them to be taken to Shlisselburg that night, 5 May 1887; the five leading conspirators in the latest foiled assassination attempt against a Russian Tsar. This time, only six years after revolutionaries had successfully blown up Alexander II, his son Alexander III had been the target. They called themselves the "Terrorist Section" of The People's Will (Narodnaya Volya), an organisation that in 1881 had been driven out of existence by widespread government repression, but whose flame they had nevertheless dedicated themselves to carrying forward. They had no experience of terrorism, yet alone of making bombs. As conspirators they were inept, to say the least. It was only their youth - the youngest was only twenty - and their bungling incompetence that had saved St Petersburg's Nevsky Prospekt from yet another outrage. A spot check on two of the conspirators by suspicious police agents had uncovered the crude bomb filled with bullets dipped in strychnine that was being carried by one of them inside a copy of Grinberg's Dictionary of Medical Terminology.

It might sound like the stuff of tragicomedy, but the plot's perpetrators were in deadly earnest, even if their bombs were later shown to be defective. But what had driven them to such violent action? Russia had ever been a country of extremes; a place where the opulence and extravagance of the Imperial Court underlined an endemic indifference to the privation suffered by Russia's silent and unseen masses. By European standards, nineteenth-century Russia was a backward country, its population largely illiterate and rural, its infrastructure - roads, railways and industry - lagging far behind that of the West. The vast majority of its multinational population of 180million (by World War I), in an empire covering one-fifth of the world's surface, had been enslaved by serfdom until 1861. But emancipation had done little to liberate the peasantry from illiteracy, poverty and land hunger, or to assuage the social conscience of a growing intelligentsia that passionately sought to redress the imbalances of the old order. Official corruption and repression in Russia drove such young people to seek political answers to the questions that so tormented them about Russia's position in the world. They wanted to work towards a better political and economic future, in which the peasantry and the urban proletariat would play key roles. For a while, hopes were pinned on the model of the existing village communes providing a shortcut to socialism and the institution of a democratic system. But the populist `To the People' movement of 1873-5 - an ill-judged propaganda drive by the intelligentsia among the peasants of rural Russia - had collapsed amidst widespread peasant mistrust of these newcomers and had ended in thousands of arrests, and exile for many to Siberia.

The response to official repression was the establishment in 1876 of Land and Freedom (Zemlya i Volya), the first political party to openly advocate political change in Russia. But before long the party became divided between those who embraced the peaceful path of agrarian reform and took up work in the rural areas for local government, while in 1879 a more extreme group formed The People's Will faction, embracing terrorism as a political weapon. But such extreme methods were short-lived; by the time the would-be assassins were arrested in 1887, The People's Will was a spent force. Arrested in March, the five men were held for two months in solitary confinement in the grim Trubetskoy Bastion of the Peter and Paul Fortress in St Petersburg. At their five-day trial in April, they were condemned to death.

The other prisoners on the isolation wing of the Trubetskoy Bastion heard the cell doors being unlocked the night the men were taken away to their place of execution; even thick stone walls could not muffle the resonant tread of footsteps matched by the ominous clank of the chains which bound the men hand and foot. The five men's shadows flickered and fell as they passed along the dark prison walls by the light of dingy kerosene lamps and were led out across the cobbled courtyard to the iron gate. Here the police vans - little more than cages on wheels - waited for them. They knew this would be the last time they would see the city. Just out of sight, the River Neva lapped softly along its long, flat embankment, where, on the dark and deserted quayside, a steamship waited, its tiny cabin windows curtaining the outside world from view.

The men were now on their way to Shlisselburg, a forbidding medieval fortress built on a small island looking out over Lake Ladoga, thirty-five miles from St Petersburg along the Neva. Every Russian revolutionary knew the name of Shlisselburg; it was the Russian Bastille and very few survived incarceration there. Built in the fourteenth century by the people of Novgorod, it was later captured by the Swedes and then recaptured by Peter the Great. It had gained notoriety when Ivan VI was held and murdered there in 1764. In the 1820s it became a staging post for conspirators in the Decembrist uprising on their way to exile in Siberia. But since 1884 it had served a much more specific purpose, when a special isolation prison was built within its ancient walls for the incarceration of forty of the country's highest security political prisoners. Shlisselburg was a place, it was said, from which people were only carried out; they very rarely walked. If they took you there it was either to hang you or because your death sentence had been commuted to life imprisonment. And life meant life. One way or another, you'd die at Shlisselburg.

After five hours on the steamship the green, iridescent waters of the River Neva suddenly broadened out as it flowed into the lagoons of Lake Ladoga. Here, Shlisselburg, with its white walls and towers of limestone, loomed into view in the early dawn. At the top of a tall spire shone a gilded key - the key that had given the fortress its German name from the word Schlussel. As the five men passed through the high white walls of the main entrance, the huge, two-headed Imperial eagle above it looked down on them as though ready to swoop. Inside everything seemed white and quiet and orderly - like a tiny village with its own small white church at one end. But beyond this seemingly peaceful setting there stood a two-storey redbrick building with dirty windows and two tall chimneys - the special wing for political prisoners. Inside, the poorly lit first and second floors were divided by a net to prevent suicide attempts from the top floor; connecting the two levels from one side to the other, there was a narrow walkway - a Russian Bridge of Sighs.

Ranged round the circumference were forty black iron doors leading into forty isolation cells - set like a row of coffins standing on end, for incarceration here was a living death - with only the fuzzy outline of the far horizon beyond each cell's opaque windowpane. Inside there was nothing but the overpowering stillness of solitary confinement - where the real becomes unreal and the imaginary can become so vivid that it takes on a life that confuses the senses and drives men mad. The only sounds breaking the silence were the hissing of water in pipes somewhere far below, or, in the distance, the faint tubercular cough of another prisoner. Sometimes there came the soft tap-tap of prisoners communicating with each other by their own improvised Morse code. And, sooner or later, the rattle at the door, as its peephole was slid back by the gendarme on duty.

Three days later, on 8 May, having been lulled into a false sense of security that their sentences were to be commuted, the men were woken at 3.30 a.m. and informed that they were to be executed in half an hour's time. The prison officials had been so secretive in the construction of the gallows during those intervening three days that none of the prisoners in the isolation block had known. But they only had room for three gallows, which had been made up in sections, outside the prison, and silently assembled near the main entrance, without so much as a single blow of an axe being heard.

As the rest of the prisoners slept the heavy sleep of those with an eternity on their hands, the commandant, priest and guards accompanied the five prisoners in single file to the place of execution. The condemned men were offered the consolation of a priest but all refused. There being only three gallows, they had to hang them in two batches: Vasily Generalov, Pakhomiy Andreyushkin and Vasily Osipanov embraced each other and cried out "Long Live The People's Will" before the sack was thrown over their heads and the stools kicked from under them. The condemned in Russia were not yet accorded the merciful death of the trapdoor, but a slower one, by strangulation.

After their corpses had been taken down, the other two men were brought forward. Petr Shevyrov, the ringleader of the conspiracy, pushed away the cross as the priest offered it to him, but the last man, with absolute composure, stopped and kissed it before they hanged him, too.

His name was Aleksandr Ulyanov.

Nine hundred and thirty-five miles away, in provincial Simbirsk, Ulyanov's younger brother was studying hard that day for his final, rigorous school examinations, unaware of what had taken place. That sixteen-year-old boy was the man who became Vladimir Ilyich Lenin.

Aleksandr Ulyanov's corpse had already been hastily consigned to a common grave with his fellow conspirators in the grounds of Shlisselburg before his mother Mariya, who had been lobbying the authorities for weeks to commute his sentence, learned that her son had been executed - in an announcement in a broadsheet handed out on the streets of St Petersburg. Her emotional control and fortitude, at a time when one of her daughters, Anna, was also in police custody in the city, implicated in the same plot, was extraordinary. It was a characteristic inherited by her younger son Vladimir.

Aleksandr could have appealed to the Tsar for mercy, but he refused. All he asked for in his final days was a volume of verse by his favourite poet, Heinrich Heine. He was in fact not one of those designated to throw the bomb (although, as a student of natural science, he had manufactured the nitroglycerine needed) and would have been reprieved had he petitioned for clemency. But he would not compromise his beliefs. He wanted to take on himself the burden of responsibility for the conspiracy, to be a martyr and to die an exemplary death. Tsar Alexander found his frankness "touching" but he did not commute the death sentence. Shortly after the executions, students at Aleksandr's university had rushed to bring out their own statement on the heroism of the five hanged men who had died for the "common cause". They had fulfilled their duty with absolute integrity and had `firmly upheld the banner of struggle for freedom and justice'!

Aleksandr Ulyanov was one of the last of a generation of romantic idealists devoted to the cause of the downtrodden masses, who had espoused the Russian populist movement and in so doing been drawn ultimately into a desperate act of terrorism. But despite achieving some spectacular murders of senior officials and the Tsar himself in 1881, The People's Will had ultimately been ineffectual in forcing constitutional change in Russia through the use of terrorism. In later years, Lenin, in an extremely rare public allusion to his brother's death, would state that such an act of martyrdom as Aleksandr's had not and never could achieve the conspirators' immediate and passionate aim - "that of awakening a popular revolution". A year before his death, Aleksandr had won a gold medal for his dissertation on "The Segmentation and Sexual Organs of Freshwater Annula". The young Vladimir had watched him at home, huddled over his microscope from the early hours of the morning examining slides. "No, my brother won't make a revolutionary, I thought then," he later told his wife Nadezhda. "A revolutionary cannot devote so much time to the study of worms."