South Korea will try robots as prison guards for one month. Robotic prison guards are 150cm tall and have wheels. They are designed to be humane and friendly. If the trial is a success more robots will be added. The robotic prison guards will be used mainly at night and with their censors can check the condition of a cell and report to the officer in charge. They will not be used only as cameras, they have algorithms that analyze activities and can detect abnormal behavior. Inmates cannot bribe or threat robots but they might find a way to hack them or exploit any vulnerabilities. This will bring us one step closer to a world that machines rule.