Doctor Who-Planet Of The Ood

                    Somewhat at random the doctor and Donna find themselves on a glacial planet that has been colonized by the fourth great human empire of the 42nd century. Along the way the doctor here's a melody in his mind that he recognizes as the song of the Ood,a telepathic species who he remembered acted as servants to the human empire. The Ood is dying and insists to the Doctor and Donna that the circle must be broken before his eyes turn a fiery red and he passes away.  The doctor and Donna come to a human colony run by Ood Industries where a human named Solana is about to make a presentation to a group of perspective clients regarding what are referred to as Ood servants. This is all taking place a midst several murders  committing by these red eyed Ood-who are believed to have gone rabid. After hearing the presentation at the conference,the doctor and Donna wander off to discover a massive warehouse where they not only discover grates filled with Ood but part of the truth about what is happening there: the human empire have begun to treat the Ood as their slaves.

                  It is at this time the doctor and Donna are found out not to be participants so Mr. Halpen and his Solana send their troops out to locate them. That forces the doctor and Donna into a imprisonment area where they find a group of un-enslaved Ood. It is at this point Donna learns that the Ood,unlike humans,have brains on the outside of their heads and this has the effect of mobilizing emotion and thought from outside sources-making them easier to control by others than other humanoids. When the pair confront Halpen about this, it becomes clear his Ood Industries have basically lobotomized the Ood by replacing this brain with a translator  But the doctor points out another missing piece of the puzzle,when Harplen takes them to a facility housing an enormous brain found under the surface of this world which they have been using to control the Ood.  As it turns out,the hair tonic Harplens Ood has been giving them is a transformative agent that has been slowly turning Harplen into an Ood-the transformation of which is complete with his full expose to the brain. With the Ood now free,their collective song is sent out to the Ood all over the universe and the doctor and Donna depart having made new friends.

                   In this story we actually discover one possible reason why the doctor might've been interested in taking on Donna as his assistant in the TARDIS. Thought at first coming off as a bit of a trivial person who hadn't been a success in life, we find out here that Donna's true gifts lay in her empathy and outwardly focused ego. Her distaste for her own people in the future again resorting to slavery to build their empire easily matches the doctors own moral convictions. And in one truly touching seen in this, Donna is moved to tears when the doctor allows her to hear the Ood's telepathic song because she cannot bear to hear their suffering.  Even though her discouragement in humanity's future almost makes her want to go back home,she rethinks her plan when she brings up the gusto to stand by her convictions to the cold and uncaring Haplen. The Ood themselves are a fascinating species. With their unique biology, they are very benevolent-even transforming their nemesis Harplen rather than killing him: the old "walk a mile in my shoes" ethic. Excellent story dealing with an important but sometimes uncomfortable moral dilemma.