He told tales of a stormy sea operation (5)
I believe the answer is:
aesop
'he told tales' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'stormy sea operation' is the wordplay.
'stormy' is an anagram indicator (stormy suggests disruption).
'operation' becomes 'op' ().
'sea' anagrammed gives 'aes'.
'aes'+'op'='AESOP'
'of a' acts as a link.
Can you help me to learn more?
(Other definitions for aesop that I've seen before include "Fabulous man" , "Poses as ancient Greek writer" , "Fable-teller" , "A pose by Greek writer of fables" , "satirical writer" .)