The most common and most likely answer to this crossword clue is the 9 letter word CASSETTES
I've seen this crossword clue in The Daily Telegraph
C
A
S
S
E
T
T
E
S
Buddy explains!
The straight part
We know that "Film magazines?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case film magazines? = cassettes.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 CASSETTES mean?
CASSETTES noun- A small flat case containing magnetic tape on two reels, used to record and play back audio and video material.
- Any similar small cartridge, such as for a computer disk or cassette air conditioner
- A lightproof container for photographic film.
- A modular DNA sequence encoding one or more genes for a single biochemical function.
- A set of sprockets mounted onto a splined shaft on the freehub.
- A saggar (ceramic container used in a kiln)