Lisa's Date with Density a child from Josh Weinstein's school days who everyday would get onto the bus with a piece of toast, which had Vaseline on it. A majority of the story is a reference to the film "Rebel Without a Cause". Lisa remarks that Nelson is "like a riddle wrapped in an enigma wrapped in a vest", a reference to "a riddle wrapped in a mystery inside an enigma"; this was Winston Churchill's opinion of Russia at the outbreak of the World War II. In its original broadcast, "Lisa's Date with Density" finished 63rd in ratings for the week of December 9–15,
The Riddle of the Sphinx (Inside No. 9) in his mouth. Blood splatters over the crossword and a second nina: "RIPNHS". "The Riddle of the Sphinx" is less comedic than many episodes of "Inside No. 9", drawing upon gothic themes. Several critics identified "Sleuth"—"a grandfather of sorts" to "Inside No. 9"—as a key influence. William Shakespeare's "Titus Andronicus", the 1973 horror film "Theatre of Blood", and the work of Anton Chekhov were also identified as possible influences. Chekhov and his work are referenced in the episode; Chekhov's gun is referred to in the closing seconds, while Squires identifies the gun in the episode as from a production of