The most common and most likely answer to this crossword clue is the 5 plus 2 plus 3 plus 5 letter word SNAKE IN THE GRASS
I've seen this crossword clue in The Guardian
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More clues leading to the result SNAKE IN THE GRASS
- Wind through blades creates unseen danger
- Wind, then I twisted and bent, perhaps — a hidden danger
- Almost nude, caught in transgression, gets rash about hidden danger
- Good inside? He’s skint and an arse — run, don’t trust him!
- Assange rethinks getting new disguise — as Judas?
- Ah stinger sneaks — could be this!
- A gent with rakishness, terribly unfaithful type
- The Nadderark? He’s a treacherous person
- Keen hints broadcast about a drug? A lurking menace
- “Traitor” Assange rethinks taking a new approach
Buddy explains!
The straight part
We know that "don’t trust him" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case don’t trust him = snake in the grass.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.