Sarah Jane, Clyde, and Rani are invited by Professor Rivers of the PHAROS Institute to visit Ashen Hill Manor, a supposedly haunted house. Centuries ago, Lord James Marchwood employed an alchemist named Erasmus Darkening to replenish his fortunes. However, Darkening had a reputation for abducting people, who would never be seen again. One night Marchwood's two children disappeared, never to be seen again.
- Arbitrary Skepticism: Sarah Jane scoffs at the idea of ghosts, while simultaneously encouraging a ghost hunter to have a more open mind. Because searching for ghosts is inherently more close-minded than searching for aliens. Although she was actually implied to have been wrong about the ghosts.
- The Cavalier Years: The flashbacks that deal with the disappearance of the Marchwood family, are set in 1665.
- Continuity Nod: Sarah Jane's Arbitrary Skepticism is a subtle nod to the Doctor, who constantly refuses to believe in anything supernatural, and whenever he sees magic, magical creatures, etc, is quick to dismiss them as alien or psychic powers or something.
- Electromagnetic Ghosts: This is exploited to detect the presence of ghosts more scientifically, and prove the house really is haunted. Although - as Sarah Jane is quick to point out - they aren't technically ghosts. (Or at least, that's how it seems until the final moments of the episode...)
- Haunted House: Sarah Jane, Rani, and Clyde accompany Professor Rivers to investigate Ashen Hill Manor, supposedly one of the most haunted houses in Britain. As Clyde puts it, it's "Hogwarts, Tim Burton-style".
- Large Ham: Erasmus Darkening: "ETERNITYYYY!!! I'VE LOST ETERNITYYYYYYYYYY!!!"
- Let Me Get This Straight...:Clyde: So let me get this right. If you don't believe in ghosts, Sarah Jane, and you don't believe in ghosts, Professor, then -Rani: What are we doing here?
- Names to Run Away from Really Fast: Erasmus Darkening.
- Our Ghosts Are Different: They are actually living people trapped between dimensions.
- Real After All: Throughout the show, Sarah Jane insists that there's no such thing as ghosts, and is shown that the "spooky" goings on are due to alien technology. Then the ghosts of three departed inhabitants watches her drive away.
- Clyde "ain't afraid of no ghosts."
- There's also a mention of Dracula.
- Clyde describes Darkening's lab as "Harry Potter, Tim Burton-style".
- Whole-Plot Reference: The episode is essentially The Stone Tape as a kids' show.