Giles Milton, the author of Russian Roulette (2013) has argued: "On the face of it, Lockhart was well suited to the job for which he had been appointed. He spoke good Russian and had previously served as Consul General in Moscow. Thirty years of age and in the prime of life, he was affable, colourful and endlessly entertaining.... Lockhart had many failings and he wrote about them with disarming honesty. His lack of discretion would have been a handicap in any employment, but it was doubly alarming in a diplomat... His insatiable appetite for women was another drawback."

Robert Bruce Lockhart met and married, in 1913, Jean Haslewood, daughter of Leonard Turner, of Brisbane, Australia. He also began an extramarital affair with a woman from Moscow that resulted in him losing his job in the Moscow consulate. He later admitted: "I had made myself talked about... The Ambassador sorrowfully but firmly decided... that I must go home to England for a rest."

After the outbreak of the First World War Lockhart returned to Russia. When Tsar Nicholas II was overthrown he reported on 13th March, 1917: "So far the people of Moscow have behaved with exemplary restraint. For the moment, only enthusiasm prevails, and the struggle which is almost bound to ensure between the bourgeoisie and the proletariat has not yet made its bitterness felt. The Socialist Party is at present divided into two groups: the Social Democrats and Soviet Revolutionaries. The activities of the first named are employed almost entirely among the work people, while the Social Revolutionaries work mainly among the peasantry."

Bruce Lockhart attempted to describe the different political groups, such as the Social Democratic Labour Party, Socialist Revolutionary Party, Bolsheviks, Mensheviks, and Left Socialist Revolutionarist, that were fighting for power: " The Social Democrats, who are the largest party, are, however, divided into two groups known as the Bolsheviki and the Mensheviki. The Bolsheviki are the more extreme party. They are at heart anti-war. In Moscow at any rate the Mensheviki represent today the majority and are more favourable to the war."

In his memoirs Bruce Lockhart described Karl Radek: "A Jew, whose real name is Sobelsohn, he was in some respects a grotesque figure. A little man with a huge head, protruding ears, clean shaven face (in those days he did not wear that awful fringe which now passes for a beard), with spectacles and a large mouth with yellow, tobacco stained teeth, from which a huge pipe or cigar was never absent, he was always dressed in a quaint drab-coloured Norfolk suit with knickers and leggings. He was a great friend of Ransome, and through Ransome we came to know him very well. Almost every day he would turn up in my rooms, an English cap stuck jauntily on his head, his pipe puffing fiercely, a bundle of books under his arm, and a huge revolver strapped to his side. He looked like a cross between a professor and a bandit. Of his intellectual brilliance, however, there was no doubt. He was the virtuoso of Bolshevik journalism, and his conversation was as sparkling as his leading articles."

Bruce Lockhart was recalled to London just before the Russian Revolution. He gave a briefing to George V: "Saw the King. The King was very nice and showed a surprising grasp of the situation; he however did most of the talking and during the forty minutes I was with him I didn't really get much in. He sees pretty well the need for reforms everywhere, and has a wholesome dread of Bolshevism."

Bruce Lockhart returned to Russia in January, 1918 as Head of Special Mission to the Soviet Government with the rank of acting British Consul-General in Moscow. He also had the far more secretive role of co-ordinating the activities of British spies that had been sent to the country by Mansfield Smith-Cumming, the head of MI6. This included Sidney Reilly, George Alexander Hill, Paul Dukes, Cudbert Thornhill, Ernest Boyce, Oswald Rayner and Stephen Alley. The main objective of this group was to bring about the overthrow of the Bolshevik government.

Soon after arriving back in Russia he began a relationship with Maria (Moura) Zakrveskia. Her husband, Count Alexander Konstantinovich Benckendorff, the Tsarist ambassador to London, had been murdered by the Bolsheviks. Lockhart later confessed that he was spellbound by her vitality: "Into my life something had entered which was stronger than any other tie, stronger than life itself... Where she loved, there was her world, and her philosophy of life had made her mistress of all the consequences." Lockhart made no attempt to hide his relationship with Zakrveskia and this drew the attention of Cheka.

On one occasion Lockhart and his friend, Arthur Ransome, accompanied Felix Dzerzhinsky and Yakov Peters on a raid of 26 Anarchist strongholds in Moscow. Lockhart later recorded: " The Anarchists had appropriated the finest houses in Moscow... The filth was indescribable. Broken bottles littered the floors; the magnificent ceilings were perforated with bullet holes. Wine stains and human excrement blotched the Aubusson carpets. Priceless pictures had been slashed to strips. The dead still lay where they had fallen. They included officers in guard's uniforms, students - young boys of twenty - and men who belonged obviously to the criminal class and whom the revolution had released from prison. In the luxurious drawing room of the House Gracheva the Anarchists had been surprised in the middle of an orgy. The long table which had supported the feast had been overturned, and broken plates, glasses, champagne bottles, made unsavoury islands in a pool of blood and spilt wine. On the floor lay a young woman, face downwards. Yakov Peters turned her over. Her hair was dishevelled. She had been shot through the neck and the blood had congealed in a sinister purple clump. She could not have been more than twenty." According to Lockhart, Peters shrugged his shoulders. "Prostitutka," he said, "Perhaps it is for the best."

Jan Buikis, a Soviet agent, made contact with Francis Cromie, the naval attaché at the British Embassy, and requested a meeting with Lockhart. On 14th August, 1918, Buikis and Colonel Eduard Berzin, met Lockhart. Berzin told Lockhart that there was serious disaffection among the Lettish troops and asked for money to finance an anti-Bolshevik coup. Lockhart, who described Berzin as "a tall powerfully-built man with clear-cut features and hard steely eyes" was impressed by Berzen. He told Lockhart that he was a senior commander of the Lettish (Latvian) regiments that had been protecting the Bolshevik Government ever since the revolution. Berzin insisted that these regiments had proved indispensable to Lenin, saving his regime from several attempted coups d'état.

Lockhart claimed that initially he was suspicious of Berzin but was convinced by a letter that had been sent by Cromie: "Always on my guard against agents provocateurs, I scrutinized the letter carefully. It was unmistakably from Cromie. The handwriting was his... The letter closed with a recommendation of Berzin as a man who might be able to render us some service." Lockhart also believed Berzin's claim that the Lativan regiments had lost all enthusiasm for protecting the Revolutionary Government and wanted to return to Latvia.

On 17th August, 1918, Moisei Uritsky, the Commissar for Internal Affairs in the Northern Region, was assassinated by Leonid Kannegisser, a young military cadet. Anatoly Lunacharsky commented: "They killed him. They struck us a truly well-aimed blow. They picked out one of the most gifted and powerful of their enemies, one of the most gifted and powerful champions of the working class." The Soviet press published allegations that Uritsky had been killed because he was unravelling "the threads of an English conspiracy in Petrograd".

On one occasion Lockhart and his friend, Arthur Ransome, accompanied Felix Dzerzhinsky and Yakov Peters on a raid of 26 Anarchist strongholds in Moscow. Lockhart later recorded: " The Anarchists had appropriated the finest houses in Moscow... The filth was indescribable. Broken bottles littered the floors; the magnificent ceilings were perforated with bullet holes. Wine stains and human excrement blotched the Aubusson carpets. Priceless pictures had been slashed to strips. The dead still lay where they had fallen. They included officers in guard's uniforms, students - young boys of twenty - and men who belonged obviously to the criminal class and whom the revolution had released from prison. In the luxurious drawing room of the House Gracheva the Anarchists had been surprised in the middle of an orgy. The long table which had supported the feast had been overturned, and broken plates, glasses, champagne bottles, made unsavoury islands in a pool of blood and spilt wine. On the floor lay a young woman, face downwards. Yakov Peters turned her over. Her hair was dishevelled. She had been shot through the neck and the blood had congealed in a sinister purple clump. She could not have been more than twenty." According to Lockhart, Peters shrugged his shoulders. "Prostitutka," he said, "Perhaps it is for the best."

Despite these claims, Robert Bruce Lockhart continued with his plans to overthrow the Bolshevik government. He had a meeting with a senior intelligence agent based in the French Embassy. He was convinced that Berzin was genuine in his desire to overthrow the Bolsheviks and was willing to put up some of the money needed: "The Letts are Bolshevik servants because they have no other resort. They are foreign hirelings. Foreign hirelings serve for money. They are at the disposal of the highest bidder." George Alexander Hill, another agent based in Petrograd, also believed Berzin was telling the truth and were in the ideal position to overthrow the Bolshevik government: "The Letts were the corner stone and foundation of the Soviet government. They guarded the Kremlin, gold stock and the munitions."

Sidney Reilly and Ernest Boyce were brought into the conspiracy. Over the next week Hill, Reilly and Boyce were having regular meetings with Berzin, where they planned the overthrow of the Bolsheviks. During this period they handed over 1,200,000 rubles. Some of this money came from the American and French governments. Unknown to MI6 this money was immediately handed over to Felix Dzerzhinsky. So also were the details of the British conspiracy.

Berzin told the agents that his troops had been to assigned to guard the theatre where the Soviet Central Executive Committee was to met. A plan was devised to arrest Lenin and Leon Trotsky at the meeting was to take place on 28th August, 1918. Robin Bruce Lockhart, the author of Reilly: Ace of Spies (1992) has argued: "Reilly's grand plan was to arrest all the Red leaders in one swoop on August 28th when a meeting of the Soviet Central Executive Committee was due to be held. Rather than execute them, Reilly intended to de-bag the Bolshevik hierarchy and with Lenin and Trotsky in front, to march them through the streets of Moscow bereft of trousers and underpants, shirt-tails flying in the breeze. They would then be imprisoned. Reilly maintained that it was better to destroy their power by ridicule than to make martyrs of the Bolshevik leaders by shooting them."

Reilly later recalled: "At a given signal, the soldiers were to close the doors and cover all the people in the Theatre with their rifles, while a selected detachment was to secure the persons of Lenin and Trotsky... In case there was any hitch in the proceedings, in case the Soviets showed fight or the Letts proved nervous... the other conspirators and myself would carry grenades in our place of concealment behind the curtains." However, at the last moment, the Soviet Central Executive Committee meeting was postponed until 6th September.

On 31st August 1918, Dora Kaplan attempted to assassinate Lenin. It was claimed that this was part of the British conspiracy to overthrow the Bolshevik government and orders were issued by Felix Dzerzhinsky, the head of Cheka, to round up the agents based in British Embassy in Petrograd. The naval attaché, Francis Cromie was killed resisting arrest. According to Robin Bruce Lockhart: "The gallant Cromie had resisted to the last; with a Browning in each hand he had killed a commissar and wounded several Cheka thugs, before falling himself riddled with Red bullets. Kicked and trampled on, his body was thrown out of the second floor window."

Robert Bruce Lockhart was woken by a rough voice ordering him out of bed in Moscow. "As I opened my eyes, I looked up into the steely barrel of a revolver. Some ten men were in my room." As he dressed "the main body of the invaders began to ransack the flat for compromising documents." Lockhart was taken to Lubyanka Prison. He later recalled: "My prison here consists of a small hall, a sitting-room, a diminutive bedroom, a bathroom and a small dressing-room, which I use for my food. The rooms open on both sides on to corridors so that there is no fresh air. I have one sentry one side and two on the other. They are changed every four hours and as each changes, has to come in to see if I am there. This results in my being woken up at twelve and four in the middle of the night."

Lockhart was eventually interogated by Yakov Peters, Dzerzhinsky's deputy at Cheka. "At the table, with a revolver lying beside the writing pad, was a man, dressed in black trousers and a white Russian shirt... His lips were tightly compressed and, as I entered the room, his eyes fixed me with a steely stare." Lockhart added that his face was sallow and sickly, as he never saw the light of day.

Lockhart, who was an accredited diplomat, complained about his treatment. Peters ignored these comments and asked him if he knew Dora Kaplan. When he explained that he had never heard of her, Peters asked him about the whereabouts of Sidney Reilly. Lockhart now knew that Cheka had discovered the British plot against Lenin. This was confirmed when he produced the letter Lockhart had personally written for Colonel Eduard Berzin as an introduction to General Frederick Cuthbert Poole, the head of the British invasion force in Northern Russia. Despite the evidence he had against him, Peters decided to release Lockhart.

On 2nd September, 1918, Bolshevik newspapers splashed on their front pages the discovery of an Anglo-French conspiracy that involved undercover agents and diplomats. One newspaper insisted that "Anglo-French capitalists, through hired assassins, organised terrorist attempts on representatives of the Soviet." These conspirators were accused of being involved in the murder of Moisei Uritsky and the attempted assassination of Lenin. Lockhart and Reilly were both named in these reports. "Lockhart entered into personal contact with the commander of a large Lettish unit... should the plot succeed, Lockhart promised in the name of the Allies immediate restoration of a free Latvia."

An edition of Pravda declared that Lockhart was the main organiser of the plot and was labelled as "a murderer and conspirator against the Russian Soviet government". The newspaper then went on to argue: "Lockhart... was a diplomatic representative organising murder and rebellion on the territory of the country where he is representative. This bandit in dinner jacket and gloves tries to hide like a cat at large, under the shelter of international law and ethics. No, Mr Lockhart, this will not save you. The workmen and the poorer peasants of Russia are not idiots enough to defend murderers, robbers and highwaymen."

The following day Lockhart was arrested and charged with assassination, attempted murder and planning a coup d'état. All three crimes carried the death sentence. The couriers used by British agents were also arrested. Lockhart's mistress, Maria Zakrveskia, who had nothing to do with the conspiracy, was also taken into custody. Xenophon Kalamatiano, who was working for the American Secret Service, was also arrested. Hidden in his cane was a secret cipher, spy reports and a coded list of thirty-two spies. However, Sidney Reilly, George Alexander Hill, and Paul Dukes had all escaped capture and had successfully gone undercover.

Yakov Peters interrogated Lockhart for several days. Giles Milton, the author of Russian Roulette (2013) has pointed out: "Lockhart found Peters a curious figure, half bandit and half gentleman. He brought books for Lockhart and made a great show of his generosity. Yet he had a ruthless streak that chilled the blood. He had lived for some years in England as an anarchist exile and had even been tried at the Old Bailey for the murder of three policemen. To the surprise of many, he had been acquitted. In conversations with Lockhart he recalled the happy years he had spent living in London as a gangster. After five days of imprisonment in the Loubianka, Lockhart was transferred to the Kremlin. Accusations continued to be levelled against him in the press and he was told that he was to be put on trial for his life. Yet the trial was continually delayed and he eventually heard that it was unlikely to go ahead."

On 2nd October, 1918, the British government arranged for Lockhart to be exchanged for captive Soviet officials such as Maxim Litvinov. After his release the remaining plotters were put on trial. They were all found guilty and Xenophon Kalamatiano and Colonel Alexander V. Friede were condemned to death. The court also passed death sentences on Lockhart, Reilly, Joseph Fernand Grenard and Colonel Henri de Vertemont, noting that "they had all fled". They would all be shot if ever found on Soviet soil. Friede was executed on 14th December but Kalamatiano was reprieved.

Arthur Ransome then received information that Horatio Bottomley, the editor of John Bull Magazine, was threatening to expose him as a Bolshevik spy. Ransome immediately contacted Lockhart and told him that Bottomley intended to describe him as a "paid agent of the Bolsheviks" and asked him for help. He pointed out that he had been asked by Sir George Buchanan to be "an intermediary to ask Trotsky certain questions, my attempts to get into as close touch as possible with the Soviet people have had the full approval of the British authorities on the spot. I have never taken a single step without first getting their approval."

Ransome went onto argue that he was under orders to provide pro-Bolshevik reports: "As for my attitude towards (the Bolsheviks), please remember that you yourself suppressed a telegram I wrote on the grounds that its criticism of them would have put an end to my good relations with them and so have prevented my further usefulness. Altogether, it will be very much too much of a good thing if, after having worked as I have, and been as useful as I possibly could, I am now to be attacked in such a way that I cannot defend myself except by a highly undesirable exposition (to persons who have no right to know) of what, though not officially secret service work (because I was unpaid) amounted to the same thing." Lockhart contacted Bottomley and the article never appeared.

Lockhart worked for the Foreign Office until 1922 when he decided to start a new career in banking. His book, Memoirs of a British Agent, was published in 1932. During the Second World War Lockhart served as Director-General of the Political Warfare Executive.

Robert Bruce Lockhart died on 27th February 1970.