Speaking of two cliffhangers for the price of one, seminal Tom Baker story The Deadly Assassin is blessed enough to feature not just one iconic cliffhanger but two. It rather makes up for its tautological title (if you think about it, surely an assassin, by nature, is deadly?). The Doctor has returned to Gallifrey to prevent the assassination of the Time Lord President. So, in the closing moments of the first episode, the viewers' jaws hit the ground when the Doctor appears to shoot the President himself. Rather than another cliffhanger of the Doctor having a gun pointed at him, it's shocking to see the Doctor doing the firing. What could he be thinking? Of course, things are not all they seem and it turns out the Doctor was framed. But just as fans were recovering from that last cliffhanger, Part 2 provided them with another belter. Venturing into the virtual reality that is the Matrix (no, not that one), the Doctor appears to be stuck on a railway line - and an old fashioned steam train is heading straight for him. Similar to the Mind Robber, this cliffhanger enjoys working outside the normal physical rules of the Doctor Who world and succeeds in delivering a good shock while it's at it.
