The most common and most likely answer to this crossword clue is the 3 letter word SIN
I've seen this crossword clue in The Times
S
I
N
More clues leading to the result SIN
- Evil is returning with nefarious leader
- Second home is something bad
- Beginning to seem cool, crime
- Something bad in grass, not good
- Lapse, not bad for sailor
- Evil in Jerusalem with love denied
- Function without energy and go badly wrong
- Wrongdoing curtailing function
- Skiing regularly leads to envy, possibly
- Wrong indicator? Not good
Buddy explains!

The straight part
We know that "Evil" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case evil = sin.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.
What does SIN mean?
SIN noun- A violation of God's will or religious law.
- A misdeed.
- A sin offering; a sacrifice for sin.
- An embodiment of sin; a very wicked person.
- A flaw.
- To commit a sin.
- A letter of the Hebrew alphabet; שׂ
- A letter of the Arabic alphabet; س
- A traditional tube skirt worn by Lao and Thai women, particularly northern Thai and northeastern Thai women.