“The only thing known concerning the Dread Pirate Roberts is that he never leaves captives alive.”

It is revealed during the course of the story that Roberts is not one man, but a series of individuals who periodically pass the name and reputation to a chosen successor. Everyone except the successor is then released at a convenient port, a new crew hired, and the former Roberts stays aboard as first mate. The constant reference to “”Captain Roberts”” establishes the new Roberts’ persona. After the crew is convinced, the former Roberts leaves the ship and retires on his earnings.

However this iteration of Dread Pirate Roberts is really Westley, who inherited the title after the previous Dread Pirate Roberts retired. Westley had grown close to his predecessor after he was captured while searching for his fortune to return to Buttercup. In an attempt to help him achieve this goal the Previous Dread Pirate thought this position would help Westley achieve his goal.”