The most common and most likely answer to this crossword clue is the 10 letter word ATROCITIES
I've seen this crossword clue in The Times
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More clues leading to the result ATROCITIES
Buddy explains!

The straight part
We know that "Wicked deeds" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wicked deeds = atrocities.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 ATROCITIES mean?
ATROCITIES noun- An extremely cruel act; a horrid act of injustice.
- The quality or state of being atrocious; enormous wickedness; extreme criminality or cruelty.
- An object considered to be extremely unattractive or undesirable.