Michelle Gomezs casting announced her as the Gatekeeper of the Nethersphere, and onset photos from the finale showed her in a modern-day Earth setting alongside the Doctor, UNIT and the Cybermen. Now Missy could be the Rani, she could be the Master, she could even be the TARDIS. But in addition to any other role she plays, it is extremely likely that she is working as an envoy for the Cybermen. When we last properly saw them, in last years Nightmare in Silver, they were all but wiped out of existence. A lone Cybermite was seen to be floating through space. Their next appearance in The Time of the Doctor showed but a few silver menaces. It is likely that the Cybermen occupy heaven, and have utilised some form of technology to transport the recently deceased (or dying) to heaven in order to harvest them. Missy could act as a conduit to greet the new inhabitants and take them to the conversion chambers. We have seen the Cybermen use humans in the past, such as Martha Jones cousin. Missy appears to have control of her inhibitions and actions, but so did Mercy Hartigan, initially. So Missy probably either works for the Cybermen, or else is attempting to save others from their clutches. There are only five episodes left until we find out the truth, but this one is probably correct. We do you think Missy is? Do you agree with any of these theories? Sound out in the comments below.
