Such lies even Hitler couldn’t tell (9)
I believe the answer is:
barefaced
'such' is the definition.
Both the definition and answer are adjectives. Maybe they are linked in a way I don't understand?
'lies even hitler couldn't tell' is the wordplay.
I cannot quite see how this works, but
'tell' could be 'bare' (baring is a kind of telling) and 'bare' is present in the answer.
The remaining letters 'faced' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
(Other definitions for barefaced that I've seen before include "Unshaven kind of blatant liar" , "Audacious" , "having just had a close shave" , "Cheeky" , "Shameless like liar, having shaven visage" .)