The Unicorn and the Wasp, one of my favorite Dr Who episodes, plays on three levels of derivation.
- The plot revolves around a murder mystery with Agatha Christie trappings (a Reverend, an Author, and a Doctor in attendance to a murder) and Ms Christie herself present and involved. This is the first level of derivation because the episode assumes our knowledge of Christie’s mystery novels.
- It is revealed that the plot’s similarity to Christie’s mysteries is not Dr Who writers just playing in someone else’s sandbox for joy, as they did with Treasure Island, but an essential plot-point. Simply, an alien has read Christie’s novels, assumed they depicted normal life, and so began committing murders to make its reality more “normal.” This is the second level of derivation–and arguable the closest an episode gets to fanfiction, specifically a cross-over fic.
- Finally, the story is inserted into Christie’s historical life, solving the riddle of her famous disappearance. This is the third level of derivation, one common to Dr Who episodes, where the Doctor is inserted into a node in history and the episode is similar to fantasy/sci-fi tinged historical fiction.
What I love other than this unbearably cute scene:
Is how this episode is multi-leveled, complex, and fun it is while remaining derivative in nearly all aspects. It demonstrates that fiction can be well-written and stand on the shoulders, rather than in the shadows, of literary giants.
Was this episode Agatha Christie fanfiction? Depends on your definition of fanfiction, but I would say: yes.
“Music washes away from the soul the dust of everyday life.”–Berthold Auerbach