All the Doctor wanted to do was show Clara around Beaumonde; all Malcolm Reynolds wanted to do was finish an important job. However, when Alliance soldiers show up, plans are changed, and Mal takes Clara hostage. The Doctor reluctantly teams up with the Alliance, who've compounded his TARDIS, to find Mal and his crew. Both are ready to do anything to protect what they care about.

Keith is just an ordinary teenager, but the other person living in his mind is not. When he's kidnapped for illegal testing, he finds himself being the test subject for project Hyde. Now he has a mutant in his head, created to be the ultimate war machine. When the laboratory releases him, he admits himself into Bayville Asylum, where a man named Charles Xavier begins to visit him.

A freshman at Bayville High witnesses mutants using their powers and is taken to the institute so that Professor X can remove her memory of the event. He discovers that the girl Lance dubbed "fish", Haddy, experiences migraines which he believes to be symptoms of the X-gene. As the condition intensifies, can they figure out what's causing it in time to save her?