Crme de la crme of joints to the east of Brentford FC (3,4,5)
I believe the answer is:
the bees knees
'crme de la crme' is the definition.
I know nothing about this answer so I can't judge whether this works.
'joints to the east of brentford fc' is the wordplay.
I cannot quite see how this works, but
'joints' could be 'knees' (knee is a kind of joint) and 'knees' is found within the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is present in the answer.
'east' could be 'e' (abbreviation) and 'e' is located in the answer.
This explanation may well be incorrect...
'of' acts as a link.
Can you help me to learn more?
(Other definitions for the bees knees that I've seen before include "Excellent thing" , "Just the very best" , "Outstandingly good thing" , "Ideal person, event" , "A corker, a humdinger" .)