Free-rein

Free-reins were a type of leg restraints controlled by the accumulator, the central computer at the Krib bank. Everyone at the Krib wore them. According to the Krib's manager Kingfish, "They allow us to go where we please and keep us safe from harm," which meant there was no crime. However, a person waiting in line to speak to Kingfish upstairs could not go any closer to him when they were worn. The IT worker Mandrake attached free-reins the nerves of the enslaved minds separated from the heads of the High Goliax, which worked as the organic processors of the Krib's speculator computer. The Tenth Doctor then switched power to the speculator, allowing the minds to be freed, and use their nerves as legs as they could return to the High Goliax. The queues upstairs also began to move. (COMIC: The Woman Who Sold the World)