The most common and most likely answer to this crossword clue is the 13 letter word RECONSTRUCTED
I've seen this crossword clue in The Guardian
R
E
C
O
N
S
T
R
U
C
T
E
D
Buddy explains!
The straight part
We know that "composed again (13)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case composed again (13) = reconstructed.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 RECONSTRUCTED mean?
RECONSTRUCTED verb- To construct again; to restore.
- To attempt to understand an event by recreating or talking through the circumstances.
- Constructed or assembled again; rebuilt or renovated