'If you do that in a screenplay, it's like neon flashing amateur, amateur, amateur!'

Richard Walter, chairman of UCLA's renowned graduate screenwriting program, talks about how screenwriters are often steered toward overly descriptive action lines.

"More writers have been ruined by creative writing teachers who said to them, 'You write so visually, your writing is just so descriptive and so visual that you should really be writing film.'

"But film is the least visual of all forms of writing.

"For example, here's a description in a screenplay of a waterfall. Here it is: 'Waterfall.' You're not going to go into the way the light plays on the foam and the spray, the way it trickles down the granite rockface. ... You could go on and on and on with that.

"If you do that in a screenplay it's like neon flashing amateur, amateur, amateur!"