2, a more free-form game with strong narrative. In 2002, the team had come up with a core gameplay mechanic idea based on three groups of forces; drones that would carry a desirable resource, protectors that would guard the drones, and harvesters that would attempt to take the resource from the drones; these would eventually bear out as the Little Sisters, Big Daddies, and Splicers in the final game, but at the time of the concept, there was no set theme. They began working on creating a setting for the game as to be able to pitch the idea to game publishers. A 2002 demonstration version was based on the Unreal Engine 2 for the first Xbox. This demonstration was primarily set aboard a space station overtaken with genetically-mutated monsters; the main character was Carlos Cuello, a "cult deprogrammer"—a person charged with rescuing someone from a cult, and mentally and psychologically readjusting that person to a normal life. Ken Levine cites an example of what a cult deprogrammer does: "[There are] people who hired people to [for example] deprogram their daughter who had been in a lesbian relationship. They kidnap her and reprogram her, and it was a really dark person, and that was the [kind of] character that you were." This story would have been more political in nature, with the character hired by a Senator. The team collectively agreed that this game was not what they had set out to make, and were having trouble finding a publisher. They considered ending development, but as news about their efforts to create a spiritual successor to System Shock 2 began to appear in gaming magazines and websites, the team opted to continue development, performing a full revamp of the game. By 2004, 2K Games, a subsidiary of Take-Two Interactive, offered to publish the game primarily based on the drone/protector/harvester concept, giving Irrational the freedom to develop the story and setting. By this point, the story and setting had changed significantly, taking place in an abandoned World War II-era Nazi laboratory that had been recently unearthed by 21st-century scientists. Over the decades, the genetic experiments within the labs had gradually formed themselves into an ecosystem centered on the three groups. This version of the game included many of the gameplay elements that would remain in the final BioShock, themselves influenced by concepts from System Shock 2. These elements included the use