Woody sent me this email last week:
The idea of writing log lines is not a problem to me- I get it. But I have never found a good resource for what Hollywood wants to see. Most log lines seem too vague or read as generic, recycled sentences that could describe anything. I don't know if I am reading industry standards or amateur hour sentences. Wondering if you have any advice on what catches your eye:...Should they be one sentence or is two OK?...Do you need details on the plot or something that generally piques your interest?...etc. Here is one I am working with as an example.
EXPOSURE- The iconic artist of the previous decade, photographer David Ansell laments the erosion of his reputation to simply being famous for being famous. The entire world is nearly turned inside out as his search for a new muse reveals a violent, ancient force and one woman's insidious plot to control it.
There are slightly different schools of thought on this, so I wouldn't be surprised if people weigh in with different opinions in the comments. To cover your first questions, I'd say to shoot for one sentence, but don't sweat it if you need two sentences to cover everything. It's also not a bad idea to include some plot details - or at least the main hook of the story and how it relates to the main character. A good trick is the TV Guide technique - write the logline the way you imagine that TV Guide would summarize the story.
Take Die Hard for example: "A New York cop tries to save his estranged wife from terrorists who have taken an L.A. office building hostage on Christmas Eve." Bam! One sentence and I know the protagonist, the antagonist, the hooks and the stakes.
The other trick is to keep it simple. Your logline is a little wordy and uses words that could come off as pretentious. Some people also say that the loglines shouldn't have character names. Given that, I might rewrite your logline as follows:
"An iconic photographer seeks a new muse in his struggle to become relevant again, but the entire world is nearly turned inside out when his search reveals a violent, ancient force and one woman's insidious plot to control it."
Right there you've got the protagonist, the antagonist, the protagonist's quest and the main conflict of the story. This also suggest that the genre of the script is a supernatural thriller of sorts - is that assumption accurate? Giving your reader an idea of exactly what genre you're playing in is another good idea, some would say an essential one. If I know my boss is looking for a female-driven romantic comedy with a sports element, you don't want me mistaking your pitch for a male driven baseball drama.
I hope this was helpful.