10. The Long Game
The problems with The Long Game is that it rushes what could've potentially been a goldmine of a plot. Yes, it works as a standalone and as a way to set up the finale, but it dropped the ball insofar as it didn't explore the whole 'failed companion' storyline represented by Adam Mitchell. Because of this, it felt like a gigantic missed opportunity. Let me explain. Underneath The Long Game's media-manipulation story is another one about a failed companion called Adam Mitchell, who was picked up in the previous 'Dalek.' Overcome by the knowledge available in the future, he sends a message home. Obviously, the Doctor takes umbrage with this so sends him back to his time with a click-operated hole in his forehead. I don't know about you, but I think Adam could've been so much more, yet he's effectively shot down by timing having only been in the TARDIS since the previous episode, we know nothing about him so can't really care when he meets his 'end.' If we'd been given a few episodes with the bloke, learnt his foibles and that he had a good heart really (something of which 'Dalek' failed to convince me), we might've actually felt something when he succumbed to his information-lust. Yet we only got the one episode, and nobody cared. The whole gradual corruption of a companion thing might've been something to build a season around. Yet it turned out to be throwaway just an excuse to stick a revolving door on the TARDIS and not interrupt the Rose-Doctor love-in. A shame.