In the majority of games, you’re either in the crowd for the execution or heading for the chopping block, rather than being the person under the executioner's hood. Well, Lesser Evil Games are putting players in charge of the headsman's axe, with their horror RPG The Executioner.
For slightly cheerier stories, have a gander at this list of great PC RPGs.
Set in a grimdark fantasy world, The Executioner has players taking the role of a royal executioner and torturer. You are given orders from your employer to extract confessions from people that have been sentenced to death, and then dole out their demise in an appropriate fashion. The judge has their motive and the jury have made their decision; it is up to you to gain a signed confession by any means necessary.