The most common and most likely answer to this crossword clue is the 6 letter word ADSORB
I've seen this crossword clue in The Daily Telegraph
A
D
S
O
R
B
Buddy explains!
The straight part
We know that "Get attached to film" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case get attached to film = adsorb.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.
What does ADSORB mean?
ADSORB verb- To accumulate on a surface, by adsorption