A duo of paranormal investigators attempt to contact a ghost residing in a mansion in 1974. Seeing as this is Doctor Who, we all know that the Doctor will immediately tell us that ghosts do not exist and quickly break down how science can explain this phenomenon. After Clara notices that all photos of the ghost show her in the same pose, the Doctor sets off to piece together this mystery. With the help of the TARDIS (and the return of his space suit from “The Impossible Planet,” “The Satan Pit,” and “The Waters of Mars”), they take a trip spanning from the beginning of Earth to its destruction, always taking a picture at the same location as the mansion. Once he returns to 1974, they compare the photos from across the millennia and learn that the ghost is not frozen in time, but rather, she is moving extremely slowly. The ghost is actually a woman trapped in a pocket universe where time works differently—millions of years for us is mere minutes in this other realm. This other universe is collapsing and bleeding back into our own, causing the ghost to appear.
In a humorous moment, the Doctor uses some equipment to enhance their techniques to contact the ghost. In his usual fashion, he quickly explains away the equipment by saying that, “It amplifies your natural abilities like a microphone . . . or a pooper scooper.” While this, in itself, is not really integral to the plot, it did make me laugh and gave me the impression that Neil Cross is quite possibly a fan of Marshall McCluhan, which is always a positive in my book.
It turns out that the Doctor had an alternative motive to investigate this haunted mansion. He utilized a similar tactic back in “The Rebel Flesh” and “The Almost People” to learn more about Amy's ganger avatar. This time it pertains to the mystery surrounding Clara. It does not seem like we learned anything new on this front, but perhaps once we get the answers, we can look back on this episode and realize a vital piece of information upon rewatching.
It is not new information, but Clara does tell the Doctor that she thinks the TARDIS does not like her. During this conversation some mysteries about the TARDIS arise, as well. When Clara enters the TARDIS, she searches for a place to hang her wet umbrella, but to no avail. The Doctor is surprised by this and responds with confusion as to where the coat hanger has disappeared to. Observant fans know that the Doctor keeps a coat hanger next to the TARDIS door (yet typically he haphazardly tosses his coat on the railing). A missing coat hanger may seem insignificant; however, if the TARDIS is changing and the Doctor is unaware, it is probably not a good sign. Additionally, we heard the Cloister Bell ringing during this episode. The Cloister Bell is the alarm system for the TARDIS; typically, it is heard during potential universe-annihilating events such as paradoxes. Perhaps these questions are related to Clara's mystery or they could be just inciting events for next week's episode entitled “Journey to the Centre of the TARDIS,” where it appears that there is definitely something wrong going on with the TARDIS.