Here's a summary of Fenella Greenfield's recent talk at the London Short Film Festival 2015 about the top ailments she finds in screenplays she's asked to give feedback on.
Most stories have one main central character and about four ancillary characters. If your cast list is looking like a telephone directory - prune.
First act: a rom-com; middle act: a slasher movie; final act: an interplanetary showdown? If the answer to this is 'yes' join the club - genre mash-up its one of the most common problems we see in scripts.
If we can't see it don't write it. For example, don't write: 'As he enters the room she remembers that childhood playground encounter when, cruelly, he shoved her from the swing.' Have mercy on the actress asked to 'act' that.
Goals like, 'She believes we're on the edge of an environmental catastrophe' can't be seen on screen. A goal like, 'She's travelling to a landfill in Indonesia to research a piece for the Sunday Times Colour Supplement' can.
While its true some movies are 'ensemble' pieces consisting of a gaggle of central characters, most have one strong central character who drives forward the action and is on screen at least 85% of the movie.
'But', you might be saying to yourself, 'I don't want to write some tedious agitprop, award-winning, but coma-inducing polemic' . . .
THE ONLY PLACE TO TALK ABOUT THE CRAFT OF SCRIPTWRITING.