Pictured: Ed Harris as the Man in Black.HBO

Westorld has just a few more episodes to go before the first season winds up, and one of the biggest mysteries of the show is Arnold, the co-creator of the hosts in Westworld amusement park. All we know is that he wanted to destroy the park before everything went south, but he did not succeed and this might be what prompted him to kill himself.

Although he is not around in physical form, Arnold seems to have implanted his consciousness into another host's programming, making it easy for the android to corrupt other hosts and succeed in destroying the park.

So, who could be helping a dead Arnold tamper with the programming? Westworld Reddit forums are filled with theories on who this could be, with one user claiming that Arnold is not really a person, but is one of Ford's invention who became too wise for his own good.

Here's the reasoning: "My line of thinking as of late has been that Ford was the human inventor of an AI he named Arnold, and they were partners in designing/building the park. And in the time since whatever the cataclysmic event was, Ford has been able to limit/control Arnold's activity. (Perhaps this is why he insists on keeping all code/hosts in the park, where they can be free under his control). It might even be possible that he limited Arnold's AI to Bernard's host body early on, and that's why he's constantly paranoid about how much Bernard knows, and refers to him as having a 'sensitive disposition'."

Meanwhile, another theory suggests that Arnold is really the Man in Black, who is yet to be given a name in the show. Ed Harris' character has been a regular at Westworld for about three decades and he is quite familiar with a number of old hosts such as Teddy, Dolores. Those in charge of the amusement park also do not prevent him from acting out his will, which has given momentum to this theory.

It is not immediately known if the Arnold mystery will be solved in the season finale, which will air on December 4.

Westworld airs Sundays on HBO and Tuesdays on Star World Premiere HD.