Remove clothes and German actress drops pretence (7)
I believe the answer is:
undress
'remove clothes' is the definition.
(I've seen this before)
'and german actress drops pretence' is the wordplay.
'and german' becomes 'und' ('and' in German).
'drops' is a deletion indicator.
'pretence' becomes 'act'.
'actress' with 'act' taken away is 'ress'.
'und'+'ress'='UNDRESS'
(Other definitions for undress that I've seen before include "Remove clothes, strip" , "Sunders (anag)" , "Take off clothing, strip" , "Divest of clothes" , "Nudity" .)