 Donald Sinden's character was based on the true-life exploits of Sub-Lieutenant Robert Aitken, who died a few weeks after Sinden.In his first autobiography, "A Touch of the Memoirs", Sinden said "I had to re-enact a deed originally performed by Commander Donald Cameron.While his X Craft was being towed across the North Sea, the cable picked up a floating mine which then moved along the cable and made straight for his midget.