The Riddle of the Sphinx (Inside No. 9)
A cryptic crossword episode with deadly consequences.
"The Riddle of the Sphinx" is the third instalment of the third series of the British dark comedy programme *Inside No. 9*. Broadcast on BBC Two on 28 February 2017, it was penned by the show’s creators, Steve Pemberton and Reece Shearsmith, with Guillem Morales directing. The action takes place in Cambridge and features Alexandra Roach as Nina, a woman after the answers to the *Varsity* cryptic crossword; Pemberton as Professor Nigel Squires, who compiles the puzzle under the alias ‘Sphinx’; and Shearsmith as Dr Jacob Tyler, a fellow Cambridge scholar. The episode opens on a stormy night as Nina lets herself into Squires’s rooms, is caught, and then receives a lesson from him in solving cryptic clues.
The narrative centres on the clues and solutions of a specific crossword. The concept for a crossword-themed episode originated with Pemberton, a long-time fan of cryptic puzzles, who drew particular inspiration from Alan Connor’s non-fiction book *Two Girls, One on Each Knee: The Puzzling, Playful World of the Crossword*. Pemberton himself set the crossword featured in the episode, which appeared in *The Guardian* on the day of broadcast, credited to “Sphinx”. This puzzle contains multiple ninas—concealed messages or words. One nina is crucial to the plot, a second was discovered by accident and then woven into the story, and a third serves as an *Inside No. 9* in-joke.
The episode leans more toward gothicism than comedy, with influences including Anthony Shaffer’s 1970 play *Sleuth*, the work of Anton Chekhov, and the 1989 film *The Cook, the Thief, His Wife & Her Lover*. Critics received it extremely well, praising its writing and meticulous production detail. Commentators described it as very dark and likely the cleverest *Inside No. 9* episode to that point. Roach’s performance and Morales’s direction also earned acclaim.
**Plot**
On a stormy night, Nina enters a Cambridge room and is discovered by Professor Nigel Squires, who holds an unloaded gun. She explains that her boyfriend Simon loves cryptic crosswords but she can never assist him. She has come to Squires—a classicist who sets *Varsity*’s crossword as the Sphinx—for the answers to the next day’s puzzle. Squires begins teaching her: “I teach wild creature without hospital building” yields ARCHITECTURE, Simon’s subject. They move to the next day’s clues, filling a large grid.
Quick Facts
- Series
- Inside No. 9
- Series No
- 3
- Writer
- Steve Pemberton / Reece Shearsmith
- Director
- Guillem Morales
- Editor
- Joe Randall-Cutler
- Airdate
- 2017-02-28
- Length
- 32 minutes
- Guests
- Alexandra Roach as Nina
- Prev
- The Bill
- Next
- Empty Orchestra
Facts from the source article.
Lore & Background
The plot of "The Riddle of the Sphinx" revolves around the clues and answers to a particular crossword puzzle. The idea to focus an episode on crosswords came from Pemberton; he had long been a fan of cryptic crosswords, but particular inspiration came from Two Girls, One on Each Knee: The Puzzling, Playful World of the Crossword, a non-fiction book by Alan Connor. The crossword featured in the episode was set by Pemberton, and was published in The Guardian on the day the episode aired, credited to 'Sphinx'. This crossword contains multiple ninas — hidden messages or words. Along with many of the crossword's answers, one nina is integral to the episode's plot. A second was introduced accidentally, and then incorporated into the episode. A third nina is an Inside No. 9 in-joke.
Influences for the episode, which emphasises gothicism over comedy, include Anthony Shaffer's 1970 play Sleuth, the work of Anton Chekhov, and the 1989 film The Cook, the Thief, His Wife & Her Lover. The episode was written in the summer of 2015, one of the last of the series, and was filmed in December that year. Most of the episode was filmed in Langleybury, a country house in Abbots Langley, Hertfordshire, which had previously been used for the Inside No. 9 episodes "The Harrowing" and "Séance Time", as well as the house of Oscar Lomax in the Shearsmith and Pemberton television series Psychoville. The opening exterior shot was filmed in a court of Gonville and Caius College, Cambridge.
Reader's Guide
Critics responded extremely positively to the episode, lauding its writing and the precise attention to detail in the production. Commentators noted that the episode was very dark, and probably the cleverest episode of Inside No. 9 to date. Roach's performance was praised, as was the direction of Morales. The episode was characterised by Pemberton as a thriller in the style of Anthony Shaffer's 1970 play Sleuth, while Shearsmith identified the episode as particularly theatrical, in the style of Sleuth and Ira Levin's 1978 play Deathtrap. BBC executives, according to Shearsmith, saw the episode as a cross between Sleuth and Willy Russell's 1980 play Educating Rita that read as if it had been authored by psychopaths. The executive producer Jon Plowman suggested that the first half of the episode plays out like a radio play. The episode's intricate crossword puzzle, with its multiple hidden messages, and its dark, gothic tone, have made it a standout entry in the series, demonstrating the programme's ability to blend clever wordplay with a tense, theatrical thriller narrative.
Did You Know?
- The episode contains multiple ninas (hidden messages or words); one was introduced accidentally and then incorporated into the plot.
- The episode's final run-time is 31 minutes and 35 seconds, longer than the typical half hour for Inside No. 9.
Frequently Asked Questions
What is The Riddle of the Sphinx?
It is the third episode of the third series of the BBC dark-comedy anthology Inside No. 9, first broadcast on 28 February 2017. The episode is a thriller-comedy set in Cambridge that revolves around a deadly cryptic crossword published in the Varsity newspaper.
Who is in the cast of The Riddle of the Sphinx?
Alexandra Roach stars as Nina, a woman desperate to track down the answers to the Varsity cryptic crossword. Steve Pemberton appears as Professor Nigel Squires, the scholar who compiles the puzzle under the pen name 'Sphinx,' while Reece Shearsmith plays Dr Jacob Tyler, a fellow academic at Cambridge.
How does The Riddle of the Sphinx end?
Nina ultimately uncovers the lethal link between the crossword clues and a real murder, exposing the true identity hidden behind the 'Sphinx' alias. The episode closes on a dark, twist-laden note that is characteristic of the show's signature storytelling.
Who wrote and directed The Riddle of the Sphinx?
The episode was written by the programme's two creators, Steve Pemberton and Reece Shearsmith, and directed by Guillem Morales. It was produced for BBC Two as part of the third series.
What makes The Riddle of the Sphinx stand out in the Inside No. 9 canon?
It is the most structurally puzzle-driven entry in the series, building its entire narrative around the mechanics of a cryptic crossword rather than a single location or character. The Cambridge academic setting combined with a stormy-night framing gives it a distinctly gothic-thriller tone compared to many other episodes in the anthology.
More in Inside No. 9 episodes 1-24
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