The most common and most likely answer to this crossword clue is the 4 letter word SCUM
I've seen this crossword clue in The Daily Telegraph
S
C
U
M
More clues leading to the result SCUM
- Despicable people in dirty film?
- Worthless types, a hundred in total
- Son combined with mother
- Heads for seedy cinema usually marketing dirty film
- Riff-raff making unpleasant film
- Film set in Ceausescu mansion
- Undesirables charge to take drug
- Sea ——-free? It makes surface seem tidied up
- Problem involving a hundred despicable people
- A few heard about Chaplin’s first dirty film
Buddy explains!
The straight part
We know that "film on liquid" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case film on liquid = scum.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 SCUM mean?
SCUM noun- A layer of impurities that accumulates at the surface of a liquid (especially molten metal or water).
- A greenish water vegetation (such as algae), usually found floating on the surface of ponds
- The topmost liquid layer of a cesspool or septic tank.
- (chiefly US) semen
- A reprehensible person or persons.
- To remove the layer of scum from (a liquid etc.).
- To remove (something) as scum.
- To become covered with scum.
- To scour (the land, sea etc.).
- To gather together, as scum.
- To startscum or savescum.