Those making amateurish films all about first season on Red Rock mostly at graduate college (10)

'those making amateurish films all' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'about first season on red rock mostly at graduate college' is the wordplay.
I cannot really see how this works, but
'about' could be 'ca' (abbreviation for 'circa') and 'ca' is located in the answer.
an anagram of 'red' is 'rde' which is within the answer.
'college' could be 'c' and 'c' is found in the answer.
The remaining letters 'mors' is a valid word which might be clued in a way I don't understand.
This may be the basis of clue (or it may be nonsense).

Can you help me to learn more?