"Dark Water" left Doctor Who in a position to deliver one of the best season finales that Doctor Who has ever had, with the monstrously evil Missy having seemingly already put her plan into action, Danny Pink trapped in the Nethersphere, about to delete his emotions and Clara trapped in a room with a Cyberman. There are so many places to go from here, and the no doubt emotional story of Danny confronting the child he killed could have taken up half an episode in itself.
Instead, "Death in Heaven" fails to deliver on any off these cliff hangers in any real way, instead choosing to take the final episode of both the season and the two-parter in an entirely different direction. What could have
been a finale compromising of three separate story threads
instead opted to tie them all together into one anti-climactic and
ultimately unsatisfying ending.
A lot of what was set up in "Dark Water" ends up being invalidated by the direction that "Death in Heaven" chooses to go. The first half of the episode seem to be made up entirely of events that move characters from where they are to where they need to be in order for the finale of the episode to work, most of them falling unconscious at some point to speed up that process. A lot of "Death in Heaven" feels forced and unnecessary, creating an episode that feels like the ending was written first, and then worked backwards from there, a far cry from the way that "Dark Water" developed naturally.
A large part of this forced feel can be put down to the episodes focus on themes over story. Scattered throughout parts of this season has been the idea of both The Doctor as an Officer and the question of whether or not The Doctor is a good man, and although "Death in Heaven" attempts to provide some kind of resolution to these ideas, the season as whole never stressed them enough in the first place. We get a small montage of clips from this season that intend to highlight both of this themes during the finale, but this only goes to demonstrate that there simply hasn't been enough focus on these ideas throughout, using just 2 or 3 episodes each time to remind people that these are issues that The Doctor is supposedly facing. The result is that the story itself is forced into going places that feel unnatural in order to resolve ideas that the rest of the season never really explored.
None of this is to say that the episode itself fails on every level. Despite these problems, the finale of this episode still manages to feel like a real ending to a certain aspect of the show, and still manages to elicit and emotional response from the audience thanks to fantastic performances from Samuel Anderson, Jenna Coleman and Peter Capaldi, each of them giving a layered performance that takes the material and makes it better than it should be. What could have been a fairly ridiculous ending to the plot of "Dark Water" and "Death in Heaven" ends up working thanks to these performances alone.
Missy ends up being a truly dangerous villain as well, seemingly written specifically to counter the argument that no one ever really dies in Doctor Who. She personifies the idea of a psychopath throughout this episode, with Michelle Gomez's performance resembling the love child of Mary Poppins and The Joker, killing for fun and remaining unpredictable right up until the resolution of the plot. She makes a far bigger impact than her limited screen time would have otherwise indicated, and will most likely remain one of the more memorable villains that New Who has offered.
The best parts of "Death in Heaven" happen after the plot of the episode has been resolved and we get to spend some time seeing how the events of this particular story have affected the characters involved, but it isn't enough to excuse the confusing and poorly written main story. There
are plenty of little niggles that should have been ironed out - the
guest star has nothing to do, the CGI varies in quality throughout, the
Cybermen never feel dangerous enough to justify their inclusion, nothing
is explained in good enough detail to really make sense - and it all
ends up feeling empty and unfulfilling, the exact opposite of what a season finale should be.
"Death in Heaven" does more wrong that it does right, and ends the season with an episode
that feels like a first draft, rather than a finished product, especially disappointing after the set-up of the excellent "Dark Water". It's not a terrible episode, it's just surprisingly unengaging for a season finale, and despite some great performances and some genuinely meaningful ramifications for the characters involved, ends up being one of the more forgettable episodes that this season has offered.