3. River Song
Let us take a moment for the River Song haters to curse me up and down and get it out of their systems. Feel better? Well probably not but heres my reasoning. Whether you relate to River Song the character or not, Alex Kingston the actress is superb at playing her. The chance to see Miss Kingston create a new dynamic with a different Doctor is just too delicious to pass up. River Song has become a kind of guiding force at this point the outsider who comments on the action and occasionally interacts with the main characters. Its interesting because as River has developed she has become more like the Doctor the driving force behind the action; the manipulator who uses others to do their will. The Doctor may think River is tucked away neatly on a shelf but I have a feeling she and Steven Moffat have other plans. I look forward to finding out.