In S02.E07-"The Marchioness" an irregular character, with distinctly epicurean proclivities, arrives in the context of expanding their empire with a new establishment to be named "Diogenes".
What/Who/Why now?
Not, as I'd first thought, 'Dionysus' the Greek God of Wine, Fecundity & Theatre (co-opted as Bachus / Liber by The Romans), which could've been appropriate, but instead "The Cynic" amongst the ancient Greek thinky/do-ey types.
https://en.wikipedia.org/wiki/Diogenes
This a key aspect of Sherlock's character IMNSHO, plus other similarities; a healthy / pragmatic disrespect for authority, being not so much 'Of The World' but still 'Worldly', unorthodox street theatre with purpose & warehousing old cold case files etc.
There IS a confirming clue in the early dialogue, with Ancient Greece rather randomly being mentioned. Or not.
Also; it turns out to be ACD canon- https://www.reddit.com/r/elementary/comments/1x4y70s/which_conan_doyle_nod_in_elementary_took_you/ & possible inspiration for SH Inktober- https://www.reddit.com/r/elementary/comments/1wu0zzq/sherlock_holmes_inktober/ .
Funny Bits:
- A dichotomy between two instances of inter-gender greetings. "It's European!".
- Sherlock almost visibly biting his tongue after a reproachful look from his partner, although he only briely abstains from cutting comments (the ep starts in an NA meeting).
Other could be clever bits:
-As 1/2 explained in show, a 'Marchioness' is the "Her Indoors" of a Marquis (as in de Sade), the titled local guvna of a 'March', ie a border-land / buffer region, as in historical DenMARK or The Welsh Marches. This Marchioness was indeed 'in between' & a key actor here is Welsh (properly so in "Notting Hill" (1999)).
- A Nigella in a foodie & plummy Brit setting (ie not quite N. Lawson).
- It seems unlikely there's any 'March of Loudwater' in Suffolk (the UK County) as it has a pretty flat landscape, while Sherlock's contribution to an open discussion at NA was partly about the noisesome nature of our times.
Speaking of cynicism / skepticism, there's a slight Sherlock semblance with the 2002 UK, not renewed, telly series https://en.wikipedia.org/wiki/Believe_Nothing .
A late Rick Mayall joint; the whacky adventures of another Egghead in a Shadowy World, with his actual valet Brian Albumen (Get it? x2).
I remember that it was funny & twisty enough, but quite OTT in premise & dramaturgy.
The image is Rodin's sculpture "The Thinker" (1904) which could be influenced by Ancient / Classical Greek statuary & philosophers via The Italian Renaissance (the orange masked TMNT), & anyway, "The Over Thinker" renderings are more Dali & The Mummy.
I was gunna go with a diagram of Pythagoras Theorem, but that'd've been too (two) 'oblique'.