Bayonetted and shot by drunken assassins, the slaughter of the Russian royal family shook the world.
Now a new book reveals in compelling detail the horrifying final days of the Romanovs.
As the light faded, a train halted in the siding near the remote railway station of Lyubinskaya on the Trans-Siberian railway line.
Gunned down: The Tsar and Tsaritsa with their five children who were executed by the Bolsheviks
It was the evening of April 29, 1918, and there was nothing outwardly remarkable about these first-class railway carriages, except the presence of a heavily armed guard outside their doors.
Inside sat a family whose faces have been immortalised through history book pictures.
Four pale girls, in white lace, their hair tied back with satin ribbons. A sickly little boy in a sailor suit.
This was the moment of truth for the Romanovs, the Russian Imperial Family deposed by the Soviet revolution.
Now, they were making their final journey. The young and beautiful Grand Duchesses, Olga, Tatiana, Maria and Anastasia, sat beside their mother, the haughty Tsaritsa Alexandra, granddaughter of Queen Victoria.
The young Tsarevich Alexey lent on his father, the former Tsar Of All The Russias, Nicholas Alexandrovich Romanov. The engine started, and the train took a decisive turn.
The lingering hope inside Special Train No. 8 evaporated. The train was lumbering not towards a trial in Moscow or foreign exile, as they had believed, but to the bleak Urals.
The Romanovs were being taken to Ekaterinburg, the historic hub of Russia's old penal system.
There they would face a firing squad just 78 days later - and exactly 90 years ago this week.
To coincide with that anniversary, their last wretched days have been chronicled in an explosive new book.
Using previously overlooked documents and witness accounts, it tells the story of the family's final moments in unprecedented detail.
So just how did these most aristocratic of aristocrats fall so decisively from glory?
A man of limited political vision and ability, Nicholas was an unlikely king. Even in stature, at 5ft 7in, he was lacking.
Fatally, he turned a blind eye to social unrest. He left his deeply unpopular wife, Alexandra, in effective political control.
She was increasingly spellbound by Grigory Rasputin, the charismatic 'holy man' she believed could save her haemophiliac son Alexey from bleeding to death.
Faced with escalating political turmoil, Nicholas believed he had no option but to abdicate 'for the good of Russia' in 1917.
He did so also because he believed it would guarantee the safety of his beloved family.
Again, in this he proved calamitously naive. The family were initially placed under house arrest and then transferred to a small rural town, Tobolsk, where they retained a substantial entourage of 39 courtiers and servants.
They brought many of their Imperial Palace treasures with them, including leather-bound volumes of photographs and vintage wines from the court cellars.
Eventually, the new revolutionary high command decreed that such privilege could not be allowed in the emerging communist state.
Instead, a house in Ekaterinburg was secretly prepared. It would be a far cry from the sumptuous winter and summer palaces, banqueting halls and glorious gardens the Imperial Family had previously enjoyed. Ominously,
it would be referred to by a Bolshevik euphemism, dom osobogo znachenie - The House Of Special Purpose.
Stepping off the train in Ekaterinburg after a bone-rattling five-day journey, an exhausted Nicholas and his wife were received into the hands of local soviets, along with their doctor, maid, valet and footman.
As their car drew up to The House Of Special Purpose, they looked their last on the outside world.
It was Passion Week, and the Easter bells of the Orthodox Church rang out across the city.
As the gates to his new prison slammed shut, the Tsar was curtly told: 'Citizen Nicholas Romanov, you may enter.'
From now on, there would be no more acknowledgement of Romanov status and titles, much to the Tsaritsa's disgust.
Gradually, the Imperial Family settled in to their new lodgings, a private house which, though hardly a palace, was nonetheless regarded as one of the most modern in the city, as it possessed a flushing toilet.
Hidden behind a high wooden fence, its windows blacked out, it was now a gloomy prison. The Romanovs were confined to a suite of five rooms.
Spirited and bored, the Romanov girls, aged between 17 and 22, ignored warnings not to peek out of an unsecured top-floor window, until a sentry fired a warning shot at Anastasia's head.
The young princesses' clothes were becoming increasingly threadbare - there were no more white dresses and pretty hats like they used to wear every summer at their palace in the Crimea, a seaside paradise where the air was thick with the scent of roses and honeysuckle.
Lively and vivacious, they still beguiled their guards, however, with one saying they could not have looked prettier 'even if they had been covered in gold and diamonds'.
The family were allowed to keep their bed linen, bearing personalised monograms and the Imperial crest, as well as fine porcelain dinner plates bearing the name Nicholas II.
Alexandra had also brought supplies of her favourite English eau de cologne by Brocard, as well as cold cream and lavender salts.
These were not the only potions on which the Tsaritsa was reliant. Plagued by migraines, heart palpitations, insomnia and sciatica, she was hopelessly addicted to a whole range of drugs.
She had long ago admitted to being 'saturated' with Veronal, a barbiturate. She also took morphine and cocaine for menstrual pain.
It has been speculated that the Tsar, too, was cushioned from reality by narcotics. It was said that his childlike indifference to losing the throne was the result of smoking a mixture of hashish and the psychoactive herb henbane, administered by a Tibetan doctor, recommended by Rasputin, to counter stress and insomnia.
Life in The House Of Special Purpose was severely restrictive. They were not allowed visitors, nor to go outside except during a proscribed hour.
And they were to talk no language other than Russian 54 - the Tsaritsa liked to speak to her children in English.
However, she refused point blank to obey an edict to ring a bell every time she went to use the bathroom.
Daily life had become a matter of endurance. The family had one consuming obsession, however: Alexey's fragile health.
Since April, the 13-year-old had been suffering from a recurring haemorrhage in his knee, causing him agonising pain.
Doctors had already cautioned that Alexey would not reach 16 because of his debilitating illness, but he seemed now at death's door.
The family was exhausted by a relentless round of all-night sessions at his beside. Eventually, the splint was taken off his leg, and he could be carried out to the garden, but he would never walk again.
By early July, the daily ritual of life at the House had taken on a numbing predictability.
The family rose at eight in the morning, and breakfasted on tea and black bread.
The days were filled with endless games of cards, patience and the French game bezique, which was a family favourite, while Alexey played with his model ship and tin soldiers.
The family dogs, Ortino, Joy and Jemmy, provided a much-needed diversion.
During their hour in the small garden, the girls and their father would walk the 40 paces back and forth, eager to make the most of their exercise time.
It was a sorry picture: the man who had once ruled 8.5 million square miles of empire, now master of a single room of his own and a small, scrappy garden.
The evenings were filled with a meagre supper, prayers and Bible readings, more games, and embroidery and sewing 55 - the women spent long, furtive hours concealing gemstones and pearls into the linings of their dresses, to fund the life in exile of which they dreamed.
On July 4, there was an abrupt change in the House. The authorities were concerned that a rescue attempt was being plotted by royalists, and the guards were changed.
There was another reason for this, and for the Tsar and Tsaritsa, it was a shocking one.
On June 27, Maria, the most flirtatious and attractive of the Grand Duchesses, had been discovered, during an inspection by commanders, in a compromising situation with guard Ivan Skorokhodov.
He had smuggled in a cake for her 19th birthday, and their friendship had developed quickly in the boredom of the house.
Skorokhodov was sent to the city's prison, while Maria, an elegant young woman with light brown hair and mischievous blue eyes - was reprimanded by her family.
Tragically, in their final weeks together, her eldest sister, Olga, and her mother froze her out, refusing to speak to her as punishment for disgracing them.
Outside, civil war raged. The ranks of the White Army, which opposed the Bolsheviks, had been swelled by Czech deserters from the Austro-Hungarian army.
They were rapidly gaining ground on Ekaterinburg. Food in the city was rationed, and typhus and cholera had taken grip.
The mood grew increasingly ugly - 45 members of the local Orthodox diocese were murdered, their eyes gouged out, tongues and ears hacked off and their mangled bodies thrown in the river.
But inside the House Of Special Purpose, an air of unreality reigned. It was getting hotter and hotter, and the inhabitants of the building had now settled into a state of restless boredom.
The atmosphere was increasingly claustrophobic. The Tsar and Tsaritsa continued to write their diaries every evening, although there were no grand banquets, affairs of state, or court gossip to relate.
Only their joy when the frail Alexey had been well enough to take a bath. 'Very hot, went early to bed as awfully tired and heart ached more,' wrote Alexandra on Thursday, July 4, 1918.
A guard described the Tsar's 'melancholy' aspect, of outward calm and dignity, that crumpled when he though he was unobserved.
He would watch his children play, his soft blue eyes full of tears. For her part, the Tsaritsa was a broken woman. Gone were her delicate features and lovely golden hair.
The family had learnt to be stoical, but their awful fate loomed. In America, the Washington Post published rumours that they had already been executed.
In Britain, George V had withdrawn his earlier offer of asylum for the family, and three days' before the execution was blithely attending a cricket match at Lord's
In fact, the Romanovs' fate at this point hung in the balance. Bolshevik leader Vladimir Ilyich Lenin was aware that their demise would anger the Kaiser, because of the Romanov's links with the German royal family.
But his advisers were telling him that Ekaterinburg could soon fall to the Czechs, and the Imperial Family could prove a rallying point against communism.
The deeply religious Tsaritsa wrote to a friend that she and her family were: 'Readying ourselves in our thoughts for admission to the Kingdom of Heaven.'
At the House Of Special Purpose, the guard book recorded as it had for many days: 'Vse obychno' - ' Everything is the same'. But ominous preparations were in hand to ' liquidate' the Romanovs and to keep the matter a state secret.
A nearby mineshaft had been identified as a suitable burial place, and a doctor had been ordered to procure 400lb of sulphuric acid to destroy the bodies.
Tuesday, July 16 began uneventfully for the Romanovs, but their guards were putting into place the last plans for their execution, assembling an armoury of guns in order to carry out their task, and ordering 50 eggs from local nuns to help give them strength for the task ahead.
On one occasion, a laundrywoman witnessed 17-year-old Ansastasia sticking out her tongue at the head of the hit squad, Yakov Yurovsky.
And while there is no indication that the children were aware of their impending fate, two of the guards got cold feet and said they would not shoot the girls. They were sent away.
At 3pm, the family walked around the strip of unkempt garden for the last time.
After evening prayers, they went to bed. In the early hours of the following day, they were wakened and told that the White Army was approaching and might launch an artillery attack on the house.
They were to go downstairs for their own safety. The Tsar got up immediately, the women put on their camisoles sewn full of jewels and pearls, as they had rehearsed for a rescue attempt or sudden flight.
Soon they emerged, 'all neat and tidy' as one guard observed. At 2.15am on July 17, they were led down to the basement.
The Tsar was heard to turn and say to his daughters reassuringly: 'Well, we're going to get out of this place' - proof, some say, that he was a true martyr who was fully aware of the horror ahead.
Anastasia carried her sister Tatiana's little Pekinese, Jemmy, down the stairs. They were ushered into a storeroom, lit by a single naked bulb.
The windows had been nailed shut. True to form, Alexandra complained that there were no chairs.
Next, the family and their servants were lined up as for a last, sinister official photograph.
Then they were left alone for half an hour, as their assassins downed shots of vodka.
Re-entering the room, a guard read out a statement sentencing the family to death.
The faces before him registered blank incomprehension. The family crossed themselves, and a man walked towards the Tsar and shot him at point-blank range in the chest.
Other guards fired, as his body crumpled to the floor. Half drunk, the guards shot clumsily, hitting the Tsaritsa in the left side of her skull.
Next to her, poor lame Alexey, too crippled to move, sat transfixed with terror, his ashen face splattered with his father's blood.
The moans and whimpers from the floor testified to a botched job. But it was the children who suffered most.
None of the Romanov girls died a quick or painless death. Maria was felled by a bullet in the thigh, and lay bleeding until repeated stabbing in the torso snuffed out her life.
Her sisters were eventually finished off with an 8in bayonet, Olga having been shot in the jaw, and Tatiana in the back of the head as she tried to escape.
What should have been a quick, clean execution had turned into an orgy of killing, with only the thick clouds of gunpowder smoke obscuring the full horror of it.
Last of the women to die was Anastasia. A drunken guard lunged at her like an animal, attempting to pierce her chest with his bayonet.
Eventually, the head of the hit squad, Yakov Yurovsky, took his gun to her head.
Alexey alone was still alive, the young heir to the throne. He was wearing an undergarment sewn with jewels, which acted as a flak jacket. Yurovsky fired his Colt into the boy's head, and he slumped against his father.
It had taken a frenzied 20 minutes to kill the Romanovs and their servants. In the panicked moments that followed, Yurovsky's men staggered from the room, choking and coughing.
Shaking and disoriented, one of them vomited as he emerged into the cool night air.
Meanwhile, upstairs, in the House Of Special Purpose, Alexey's King Charles spaniel, Joy, barked, his ears pricked, waiting for his young master to return.
• EKATERINBURG: The Last Days Of The Romanovs, by Helen Rappaport, is published by Hutchinson at £18.99.