28. The Seventh Doctor's Hidden Agenda
From: "The Curse of Fenric"
Premiere: October 24, 1989
Rebounding from a silly, dodgy start, Sylvester McCoy's turn as the Seventh Doctor hit high gear in its second and third seasons, with script editor Andrew Cartmel implementing what came to be known as the "Cartmel Masterplan" – a notion that the Doctor was far more powerful (and perhaps more sinister) than we'd previously been led to believe. One result was this casserole of vampires, Vikings and an Alan Turing stand-in, in which the Doctor blatantly manipulates his traveling buddy in order to checkmate an ancient foe.