It’s Clue meets Who, with added wasp.
Short Synopsis
The Doctor and Donna crash an Agatha Christie dinner party in 1926, only to discover that someone (or something) is committing murders straight out of a Christie novel. The suspect? A shapeshifting alien wasp with a grudge, naturally.
Extended Storyline
We open in the Roaring Twenties: feathered headbands, elegant manors, and aristocrats with too much free time. The Doctor and Donna stumble onto a garden party hosted by Lady Clemency Eddison, where, in an extremely meta twist, Agatha Christie herself happens to be in attendance. (Because if you’re going to do a murder mystery episode, why not invite the queen of the genre?)
Naturally, murders start happening almost immediately. A professor is found dead in the library with a lead pipe (okay, not exactly, but close enough), and Christie is equal parts horrified and flattered. The Doctor is positively thrilled, declaring it’s “like Cluedo!” and practically bouncing with nerdy glee while everyone else is panicking.
Donna, meanwhile, slots right into “snarky 1920s socialite” mode, tossing out one-liners like she was born in the Jazz Age. She also bonds with Agatha Christie, proving once again that Donna is the companion who actually talks to people while the Doctor is too busy waving his sonic screwdriver around.
Then comes the episode’s showpiece: the Doctor accidentally drinks cyanide. What follows is David Tennant’s most gloriously over-the-top performance — twitching, flailing, gesturing wildly while Donna feeds him random ingredients from the kitchen. Anchovies, walnuts, ginger beer — it’s less “antidote” and more “Bake Off of Doom.” Somehow, it works, and the Doctor survives, mostly by pure comedic timing.
As the body count rises, suspicion falls on everyone, including a mysterious jewel thief known only as “The Unicorn.” But the real culprit? Lady Eddison’s secret love affair with an alien Vespiform years earlier. Their son grew up as Reverend Golightly, blissfully unaware he was part human, part giant wasp, until Agatha Christie novels “awoke” his stinger-happy instincts. So, yes: the killer is literally a giant shapeshifting wasp dressed as a clergyman. Only in Doctor Who.
The climax is pure Christie: a dramatic drawing-room reveal where the Doctor lays out all the clues, Donna provides sass, and the Vespiform loses it entirely, transforming into a buzzing monster. It chases Christie to a lake, where she throws in the “Firestone” jewel. The wasp, drawn to it, drowns in the water, and Christie collapses unconscious.
The Doctor and Donna return her to her car in 1926 — the same year she famously disappeared for 11 days in real life. The episode cheekily implies that the whole alien-wasp fiasco is why Christie vanished, with her memory conveniently wiped by a telepathic “psychic shock.” Which, let’s be honest, is still less weird than some of the actual theories historians have suggested.