in the dark

Idioms  

1. In secret, in concealment, as in This agreement was concluded in the dark . [Early 1600s]

2. In a state of ignorance, uninformed, as in I was in the dark about their plans . This metaphor often appears in the locution keep someone in the dark , meaning “deliberately keep someone uninformed,” as in They kept me in the dark about their plans . [Late 1600s] For an antonym, see in the know .

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Example Sentences

Challenging what seem to be the limits of science -- such as 'we cannot make things any smaller' or 'they will break if we do' -- is like walking in the dark.

From Science Daily • May 3, 2026

These are matters of the heart that can only be felt in the dark of the theater, watching such wonderfully realized characters weigh the cost of loving their work in a world that scarcely reciprocates.

From Salon • May 1, 2026

Perhaps they’re aquatic organisms—otherworldly cephalopods—that thrive in the dark seas of the outer solar system’s icy moons.

From The Wall Street Journal • Apr. 23, 2026

At five, she was diagnosed with LCA when her parents noticed she was struggling to see in the dark.

From BBC • Apr. 22, 2026

A sense of urgency pushed me faster and faster, and I barely registered the pain as my shins hit stray barrels and crates in the dark.

From "Glitch" by Laura Martin