Doctor Who: All 40 Steven Moffat Episodes Ranked From Worst To Best

Co-written with Peter Harness.

The concluding part, following on from the outstanding The Zygon Invasion, delivers the perfect balance of action-adventure, memorable acting performances, and portrays social attitudes that's not only relevant to our world today, but has been prevalent throughout human history.

First 007 and now 012, the Union Jack parachute has saved the lives of two iconic heroes in suitably stylish manner. And yes, that was written with an unashamed sense of pride at just how brilliantly creative we Brits really are.

The Doctor surviving a plane crash, hotfooting it to London whilst being amusingly acerbic about the city and in his reaction to Osgood's first name of Petronella, is reminiscent of when Capaldi's other popular character, Malcolm Tucker, ran about trying to solve a quickly escalating crisis in In the Loop - minus the casual swearing.

Once again we're left with the tantalising prospect of how great the Doctor and Osgood would be travelling together through time and space. Ingrid Oliver is superb as Osgood and blends intelligence and resoluteness with an admiration of the Doctor without it coming across as a fawning fangirl.

Coleman is clearly having fun playing the cold hearted, calculating and tempestuous Bonnie/Zygella, which reminds us just how good an actor she is. Plus she shows some incredible psychic touch typing skills on a smartphone. And then, of course, there’s that powerfully transcending speech by Capaldi's Doctor.