No actor is involved in this film! (7)
I believe the answer is:
cartoon
'this film' is the definition.
(cartoon is a kind of movie)
'no actor is involved' is the wordplay.
'is involved' indicates an anagram (involved can mean confusing or complex).
'no'+'actor'='noactor'
'noactor' is an anagram of 'CARTOON'.
'in' acts as a link.
(Other definitions for cartoon that I've seen before include "eg 'The Simpsons'" , "eg 'Tom & Jerry'" , "Humorous or satirical drawing" , "Drawing, maybe satirical" , "Animated drawing" .)