The most common and most likely answer to this crossword clue is the 4 plus 3 plus 3 plus 4 letter word ONLY TWO CAN PLAY
I've seen this crossword clue in The Daily Telegraph
O
N
L
Y
T
W
O
C
A
N
P
L
A
Y
Buddy explains!
The straight part
We know that "film" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case film = only two can play.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.