The public should be 'clued in' to what's happening. [=should be told about what's happening]
He doesn't have a 'clue' when it comes to fixing cars. [=he knows nothing about fixing cars]
He's totally 'clued in on' [=he knows a lot about] the latest computer developments.
(..) a densely packed swarm Of millions of stars. But they couldn't see what was at the center. One team has spent years looking for clues. High above the clouds on Mauna Kea, in Hawaii, The giant Keck telescope has the power To see right through (..)2010 TvShow: How the Universe Works Title: Black Holes Season: 1 Episode 2