It’s the year 2119, and we join an underwater mining mission. The location was once a village, but was flooded in the 20th century. The crew are examining an empty spacecraft with strange symbols carved into it.
The ship catches fire, killing Moran, the captain of the mission, in the process. But then Moran appears again as a ghost, along with a ghost which looks like an humanoid alien dressed in Victorian-like top hat and suit.
Three days later, the Doctor and Clara arrive, and the base seems empty. They encounter the ghosts, who more or less ignore them. Then the Doctor and Clara discover the spacecraft and find that the TARDIS didn’t translate the strange text. They then see the ghosts again, who pick up weapons to kill the Doctor and Clara with. We see that the ghosts can handle solid objects and can pass through walls and ceilings, but they can’t take the solid objects with them through the walls and ceilings.
The Doctor and Clara run away from the ghosts, and the crew we saw at the beginning of the episode let them into a Faraday Cage, which the ghosts can’t get through.
The crew already know of the Doctor’s existence. In fact one of the crew, O’Donnell, is a big fan. The highest ranking officer now is Cass. She is deaf, but can lip-read and uses sign language. She has an interpreter, Lunn. The rest of the crew are geeky scientist Bennett, and Pritchard, who represents the oil company financing the trip. He is only interested in the money that can be made. (“I imagine the power cells are pretty valuable… I mean powerful”).
We learn that the base artificially creates “day” and “night” (as otherwise there would be no way to tell from way down there, as its too far down for daylight to reach), and that the ghosts only come out at “night”. With it being “day”, everyone leaves the Faraday Cage. However, soon after the computer switches back to night mode. The ghosts are responsible. The TARDIS’ cloister bell sounds, so the Doctor goes back. The TARDIS wants to get away. She often is wary of anything that doesn’t make sense as far as timelines are concerned, and the ghosts really do not. As they have died, their time should have ended. The Doctor decides he is simply going to switch the cloister bell off, and continue solving this mystery.
Unfortunately for Pritchard, he chose this time to go out into the water looking for a missing power cell. He arrives back and removes his underwater protective gear. Moran’s ghost opens the airlock, drowning him. Pritchard is now a ghost, and picks up a chair, using it as a weapon. O’Donnell tries to reprogram the computer to get the ship back into day mode, and she succeeds. Prichard’s ghost disappears, and the chair he was holding drops to the ground.
Cass sees the safety of her crew as her top priority and wants them to abandon the base as soon as possible. As she puts it, the Doctor and Clara can stay “and do the whole Cabin In The Woods thing” if they want to, but as she’s responsible for the crew, she doesn’t want any more of them to die. But it turns out a distress call has already been made and a rescue team is on the way. The Doctor tells them to call it back. As nobody there made the call, it must have been the ghosts, so for whatever reason they want a rescue team there.
The Doctor comes up with a plan to trap the ghosts. Clara, Lunn and Bennett all run through corridors to get the ghosts to go after them. Eventually, using a hologram projection of Clara, the ghosts are trapped inside the Faraday cage. Using the Doctor’s sonic sunglasses to see them better and as a camera, Cass, viewing on a monitor, lip-reads what the ghosts are saying. It’s the same phrase over and over again, “The dark, the sword, the forsaken, the temple”.
The Doctor realises these are co-ordinates, and the “ghosts” are killing people as the more people they kill, the clearer that message becomes. They want the message to reach across the universe. But where specifically do the co-ordinates lead to, who are the ghosts targeting their message to, and why do they want them to go there? The co-ordinates refer to a church in the old village which was flooded. They go to look there, and when they find a stasis pod, which they can’t open. The Doctor looks at the space ship and says the strange text is the co-ordinates. This is why the ghosts didn’t try to kill the Doctor and Clara until they had read the text, and why one stopped trying to kill Lunn after finding out he hadn’t read the text. Even though people don’t understand the text, anyone who reads that text will have it imprinted on their brain, so when they become a “ghost” they’ll repeat that phrase over and over again.
Suddenly, the base becomes flooded. The computer has malfunctioned because of ghosts tampering with it, so everyone has to run to the TARDIS to escape. The group become separated when the automatic doors are locked. The Doctor, Bennett and O’Donnell are on one side, with Clara, Cass and Lunn on the other. The TARDIS can’t rescue Clara’s group, as they are too close in location to the ghosts. The Doctor tells Clara that he’s going to use the TARDIS to go back to before the flood, but he’ll soon return. Clara is optimistic that the Doctor will solve things easily and be back before they know it… but then she sees another ghost through the window. It’s the ghost of the Doctor!
Well, what a cliffhanger! It’s both a shock and leaves you desperate to find out what happens next.
The episode is peppered with funny lines. The Doctor is dismissive of the idea of ghosts existing at first, but that doesn’t mean that they won’t ever exist, because “There was no such thing as socks or smartphones and badgers until there suddenly were”.
There’s also Clara saying the reason that the Doctor doesn’t have a radio in the TARDIS is because he “took it apart and used the pieces to make a clockwork squirrel”.
Clara has speech prompt cards for the Doctor so he knows what best to say to the people he meets. My favourite was “No-one is going to get eaten/vapourised/exterminated/upgraded/possessed/mortally wounded/turned to jelly, we’ll all get out of this unharmed”.
We know the crew mostly by their surnames, but the first names of some of them are revealed during the course of the episode. Jonathan Moran, Alice O’Donnell, Tim Lunn, and … Richard Pritchard!
The sonic sunglasses seem to be gaining a substantial hatedom, and while I wasn’t keen on them at first they were used to better effect in this episode, with the Doctor using them to view objects rather than as a kind of teleportation device.
‘Under The Lake’ is an episode which fires on all cylinders. It is a very good story, with lots of plot. It’s an exciting action-adventure episode. The crew all have quite distinct personalities and aren’t just faceless cannon fodder. It’s a strong episode which does a lot right and ends with a great cliffhanger.