Everyone finished the fish said to be everywhere (3,4,3,5)
I believe the answer is:
all over the place
'everywhere' is the definition.
(I've seen this in another clue)
'everyone finished the fish said to be' is the wordplay.
I cannot quite see how this works, but
'everyone' could be 'all' (all people) and 'all' is present in the answer.
'finished' could be 'over' (over can mean finished or ended) and 'over' is located in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is located in the answer.
'be' could be 'place' (placing is a kind of being) and 'place' is located in the answer.
The remaining letters 'he' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for all over the place that I've seen before include "in disarray" , "everywhere" , "mess" , "not orderly!" , "Confused" .)