However, with gentle persuasion and assurances that it would not be edited into an ‘anti-Japanese film’, John and the BBC convinced two of his former captors to participate (BBC Written Archives Centre T56/203/1, Nagase Takashi, Letter (11th October 1968)). Both men were understandably nervous of the reactions their appearance might provoke among both the British and Japanese publics, but they were reassured by John’s guarantee that ‘In no way is this film motivated by revenge or sensationalism . . . The whole essence of this film is to collect the real opinions of Japanese, [and] British . . . who were actually on site of the railway between 1942 to 1945”’ (BBC Written Archives Centre T56/203/1: John Coast letter to Nagase Takashi (26 September 1968)). Lieutenant Takeroh Inoh, who was respected as a fair and decent camp commander, and the officer and interpreter, Takashi Nagase, travelled to Thailand and engaged in interviews at the sites of the camps, the cemetery, and the notorious bridge at Tamarkan. Another former Japanese soldier, Sergeant-Major Saito, who Toosey had to work with at Tamarkan Camp and Toosey held in high regard thereafter, was also present for part of the documentary (for Toosey and Saito’s relatively good working relationship at Tamarkan, see Summers (2006)).

John, both in Railway and his actions after the war, had shown his desire for justice rather than retribution. He had written an anonymous letter to The Times in 1947, criticising the twenty year sentence meted out to Colonel Yanagida (misspelled as ‘Yanagita’ in the printed letter) at the War Crimes trials in Tokyo. He describes Yanagida as being ‘comparatively humane’ while others who behaved far worse got relatively lighter sentences (Anonymous letter to The Times, “Japanese War Criminals” (4 January 1947)). In the documentary, John reiterates that Yanagida’s punishment was unjust.

When Inoh had been tried for war crimes, his characterisation in Railroad was used in his defence, along with the testimonies of senior British officers. John is sympathetic in his tone during these interviews, recognising that Inoh’s punishment was not commensurate with his actions, which were even-handed and humane in comparison with those of other senior Japanese.

Inoh appears reticent and nervous when John asks whether the Japanese would have respected the POWs more if they had been ‘heroes’ and had risked being shot by defying their captors and refusing to work—a scene recalled in Bridge Over the River Kwai. Inoh replies that the POWs had not in fact been shot, that it was just a threat, and that any subordination would have more likely resulted in a beating instead; John responds that ‘we were convinced that had we not started work then those machine guns would fire on us.’ This view is corroborated in the documentary by Lieutenant Colonel Alfred Ernest Knights (‘Colonel Day’), who states that officers agreed to work alongside the Other Ranks as they ‘should share in their troubles . . . [though] by doing so we had been guilty of aiding the enemy’ (See Knights (2013)). In the voice-over, John explains that it took the officers ‘three gallant minutes before we decided we would work’. As Colonel Toosey and the other commanding officers had understood, these compromises were a matter of survival.