Red herring — "A red herring is something that misleads or distracts from a relevant or important issue."

Есть эпизод Мидсомера — Blue Herrings.

Есть книга Ellery Queen Jr. — The Blue Herring Mystery.

Вот что пишет один из рецензентов эпизода Мидсомера:

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Is it just me, or was there an intentional effort with the title of this episode... a nod towards "blue haired" people? I mean, it's almost as if the writers thought of "blue hair" and "red herrings" and — BAM — created an episode full of red herrings and blue-haired (i.e.: mature) people. Maybe not. It's just the way my brain works.

slappy-jack-morgan
Review of Blue Herrings

Заинтересовавшись, я нашёл небольшое обсуждение, приведу цитаты.

cassadine1991
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What are "blue herrings"?

victorlord75
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In mystery stories, writers will install "red herrings", or a story point or event to throw a reader off track in a whodunit. Mr. Slesar said that since his viewers were wise enough to catch the red herrings that he would throw in some blue herrings that would make his mysteries more difficult to solve for viewers. Sigh. They don't make them like him anymore.

Darn
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But how is a blue herring different from a red herring? It sounds like a blue herring is the seeming denouement of a story but not, that there's one final twist.

victorlord75
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I think the difference between the two was ease of sniffing them out by the viewers. Mr. Slesar knew that his viewers figured out a red herring when they saw it, but he threw those in as any mystery writer would. He then threw the blue ones in to throw viewers off his trail, and quite often, the tactic worked. But notice, there was a plan. I do want to point out something else though. Mr. Slesar in no way underestimated his audience!

ranger1rg
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A blue herring is just another red herring. That's it.
Slesar was was just saying he wrote better red herrings. Truth is, there's no difference between the red and blue.

victorlord75
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I suppose you are correct. I didn't look at it that way, but there is still no denying that Mr. Slesar respected his viewer's intelligence.

GH: January Discussion, Page 8

P.S. Ещё встречалось где-то green herring в аналогичном контексте, но там было без акцентуации, чисто для разнообразия и многоцветья (red и blue там тоже были).

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