Jack Mills never really recovered. The injury to his head left him with constant trauma headaches. He went back to work doing light duties because he needed the money, then retired ill in 1967. He died in 1970 of leukemia, and his relatives believed the beating had hastened the end. For years afterwards, every fresh round of folk-hero coverage about the robbers stuck like a splinter in his family's memory. The man who actually swung the iron bar was never charged. Detective Inspector Frank Williams later said publicly that police identified him, questioned him at Scotland Yard, and could not bring a case for lack of evidence. None of the convicted robbers ever named him. In 2014, British Rail named Class 90 electric locomotive 90 036 "Driver Jack Mills" at Crewe station. The following year, the town named a road for him: Jack Mills Way. David Whitby, the 26-year-old second man who was overpowered at the trackside, was also from Crewe. He went back to work too. He died of a heart attack in 1972, aged 34. The trauma, those who knew him said, never left him either.

The bridge is still there, spanning a country lane near Ledburn in Buckinghamshire, on the West Coast Main Line between Leighton Buzzard and Cheddington. It is officially called Mentmore Bridge now, the name changed after the events of that morning made the old one infamous. The plan was to stop the train at Sears Crossing, where the lineside signals could be tampered with from cover, then move the locomotive and the two front carriages half a mile further south to the bridge. There the high-value-package coach could be unloaded into a waiting Austin Loadstar truck on the road below. The gang had a retired driver of their own, hired through a chain of acquaintances. He could not work the controls of the newer Type 4 locomotive. So they made the injured Jack Mills do it. He drove the train to Bridego Bridge half-conscious, blood on his face, with a man beside him in the cab giving directions.

It was a Bank Holiday weekend, which meant the Glasgow run was unusually full. The high-value-package coach normally held around £300,000 in registered mail and used banknotes from Scottish banks. That night it held £2,595,997 and 10 shillings, in 120 mailbags. The robbers had set a 30-minute time limit. They formed a human chain from the carriage door down the embankment to the truck and moved 120 sacks. Eight bags were left behind. They drove 27 miles to Leatherslade Farm, between Oakley and Brill in rural Buckinghamshire, where they had bought a hideout two months earlier. There they counted the money on the floor, dividing it into 17 shares of around £150,000 each. They played Monopoly to pass the time, with real banknotes from the haul as the currency. When detectives finally found the farm five days later, the fingerprints on the Monopoly board were what cracked the case open.

Detective Chief Superintendent Tommy Butler took charge of the London side of the investigation within four days of the robbery. He was a famously secretive, fanatically dedicated man known as the Grey Fox, who lived with his mother and worked his Train Robbery Squad until they begged him for sleep. By the autumn of 1963, most of the gang had been arrested. In April 1964 the trial ended with seven of the robbers receiving 30-year sentences, longer terms than many murderers got that year. The leader Bruce Reynolds and the silent man Charlie Wilson fled abroad with their families. Ronnie Biggs, the most famous of all of them in the years to come, escaped from Wandsworth Prison in 1965 over a thirty-foot wall, fled to Paris for plastic surgery, settled eventually in Brazil and stayed there beyond Britain's reach for decades. He returned voluntarily in 2001, aged 71, after three strokes, saying he wanted to walk into a Margate pub and buy a pint of bitter. He was arrested on landing and died in 2013.

There is a long British tradition of turning robbers into romantic figures, from Dick Turpin onwards, and the men of Sears Crossing inherited that gilding. The audacity of the planning, the size of the take, the escapes, the years on the run in Mexico and Brazil all proved irresistible. Films were made. Books were written. Tabloids ran sympathetic interviews on anniversaries. The family of Jack Mills watched all of it. So did Bill Boal, an engineer with no real part in the robbery who was convicted as an accomplice on thin evidence and died of cancer in prison in 1970. His family is still trying to clear his name. Roger Cordrey himself, one of the actual robbers, later told his son that Boal knew nothing about the crime. The story of the Great Train Robbery is two stories really. It is the spectacular criminal feat that ended the era of unsecured Travelling Post Office trains, and it is also a quieter story of injury and grief that the headlines never quite carried.

Trains still rumble across what is now called Mentmore Bridge several times an hour on the West Coast Main Line. The fields around Sears Crossing look much as they did in 1963: hawthorn hedges, sheep, the long flat run of Buckinghamshire that the train was crossing toward London when the wrong red signal showed. Most of the £2.61 million was never recovered. The robbers who lived long enough to be released served between roughly five and fifteen years inside, depending on the charges, the appeals, and the escapes. Most fell back into one form of crime or another. Several died in the 1990s and 2000s, of natural causes mostly, in beachfront bars in Spain or small houses in south London. The locomotive D326 was eventually scrapped. The high-value-package coach was deliberately burned in 1970 to keep souvenir hunters away. Carriage M30204M itself, the last physical link to the night, exists only in police photographs now.