The Doctor and his companion are beset by an alien virus that wants to conquer humankind. The virus swarm possesses the Doctor and now they battle the residents of a local hospital that were all possessed by the swarm. Their only hope lies in a clone of the Doctor. Written by
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Whatever it is I'm suffering from seems to thrive on intellectual activity.
Oh, I see. You mean that the harder you think, the more of a grip it seems to take?
Yeah. Non-thinkng seems to be the only way to shake it off, but I can't stay mindless for eternity, can I?