I concur with Nir Shelter that “Locke” is something of a one-off.

Further I would argue that ?”Locke” is not necessarily a good example for a newbie, someone trying to break into the business with their 1st sale, to emulate as their entree project, the one they hope will get their foot in the door.

?”Locke” was written and directed by someone who was already well established in the the movie business, who had a track record of produced scripts, an agent, connections ?– advantages a newbie needs for a project like this and doesn’t have. If it had been his first writing effort, I doubt if he could have gotten it made. This is something I think aspiring writers need to evaluate in pointing to this or that movie to justify the kind of story they are writing. ?At what point in the writer’s career, did he get the film that is similar to the one you have in mind, made? ?Was it is his first effort or was it a project he got green lit after he had become established in the industry?

As an aspiring writer myself, a newbie trying to break into the business, I’m leading with what I think is my most marketable idea. ?Not the one nearest and dearest to my arteriosclerotic ?heart. ?(Although I am quite passionate about my lead project — passion is a sin qua non to writing, of course.)?

fwiw

As?Dkpough1 said, ?a logline should focus on the?through line of action, or as I put it (because it gives me a useful visual metaphor) the clothesline of action on which everything else — characters, events, sub plots — hang.

In the case of “Up”, for example, everything hangs on the clothesline of the widowed protagonist’s effort to fulfill his lifelong dream to visit Paradise Falls. ? That’s it.

It’s a very meaningful dream for him, one he shared with his wife but didn’t have the gumption to fulfill while she was alive. ?The inciting incident, the loss of his property to development, sets in motion the chain of events that gives him the gumption to (finally) go his dream.

After reading your sketch of the story you are writing, one movie that might serve as a model for what you are trying to do came to mind: ” Chinatown”. ?Jake Gittes objective goal is solve the mystery surrounding the drowning of the L.A. water commissioner and the mystery of who and why somebody hired a woman pretending to be ?his wife to get Gittes to investigate the commissioner’s involvement with a mysterious young lady. ?

That’s the unity of action that drives the movie, the clothesline on which everything else hangs. ?The more he investigates, the more he discovers that seemingly unrelated events are part of one overall conspiracy connected to one man.

So what is the unity of action, the clothesline, on which everything else in your story hangs? ?As a result of the inciting incident, what does your protagonist set out to do? ?Of course, he’s going to find out there’s more to the first crime than he initially thought. ?But despite the new discoveries, the overall mystery will remain unsolved until the very end.

What is the primary mystery that he must find an answer to?

fwiw