So tactless in recording film in bank (12)

'so tactless' is the definition.
I can't tell whether this definition defines the answer.

'in recording film in bank' is the wordplay.
I cannot really understand how this works, but
'in' is found in the answer.
'recording' could be 'disc' (disc is a kind of recording) and 'disc' is found in the answer.
'film' could be 'et' (E.T. the Extra-Terrestrial) and 'et' is found in the answer.
'bank' could be 'rely' (to bank on something is to rely on it) and 'rely' is found within the remaining letters.
This accounts for all the letters.
This explanation may well be incorrect...

Can you help me to learn more?