a quote from wikipedia, about the DPR character: It is revealed during the course of the story that Roberts is not one man, but a series of individuals who pass the name and reputation to a chosen successor once they are wealthy enough to retire. When the time comes, "Roberts" and his chosen successor sail into port and discharge the crew. Then they hire a new crew, the ex-Roberts staying aboard as first mate and referring to his successor as "Captain Roberts". Once the crew grows accustomed to the new Roberts, the previous captain leaves to enjoy his retirement.