Was charged very swiftly beforehand for the face they made (10)
I believe the answer is:
expression
'swiftly beforehand for the face they made' is the definition.
The definition suggests an adverb but the answer is not.
'was charged' is the wordplay.
'was' becomes 'ex' (I've seen this in other clues).
'charged' becomes 'pression' (I can't explain this - if you can you should give a lot more credence to this answer).
'ex'+'pression'='EXPRESSION'
'very' acts as a link.
Can you help me to learn more?
(Other definitions for expression that I've seen before include "Look" , "something to say" .)