After aliens abandon an imminent victory against Earth, an alien Ally and a courageous lieutenant join forces in an audacious plan to stop the extinction of the solar system.

It seems like the inciting incident is the moment they discover why the aliens abandoned the war. That’s the bit which sets up the question and leads to the goal. That’s what bookends your story and it’s fundamental to understand the plot.

In terms of revealing a “secret” within the logline, it really depends where in the story this happens. Given that your plot is all about saving earth, therefore the majority of the film revolves around this, we NEED this in the logline. You’re burying something which leads to a complete lack of understanding about what this story is actually about. If you don’t tell the reader what the protagonist’s plan is, how are they supposed to have any idea what’s happening on screen. A logline can be used in marketing etc but it’s more commonly used as a pitching tool or a writing tool. Something which sums up the plot (or most of it) into a single sentence. It can give a reader (a producer) an idea of budget, locations, cast, etc etc. So by not telling us what’s actually happening, you’re leaving that open to interpretation. That’s never a good idea because you want their imagined version of the story to be as close to yours as possible, so that IF they read the script, they’re reading what they expect to read. So… going back to the secret – if the reveal happens at the midpoint or later, by all means exclude it BUT if it’s actually forming the bulk of the plot, you HAVE to! Otherwise you’re not really giving us a logline. A logline is a concise summary of the plot up to either the midpoint or the beginning of the final act, using (ideally) no more than 40 words and phrased as a single sentence (maybe two). It must also be VISUAL. You have to be able to imagine what it looks like on screen – film is a visual medium after all. Simply telling us there is a plan – “When a Great White starts eating the swimmers, a Police Chief must carry out his plan to stop it” – it leaves me wondering what am I actually going to be watching.

Where are you getting The Matrix logline from?

Re: the first sentence – the examples you’ve used are telling the reader about the world this film is set which is essential to understanding the story. Without “in a distant galaxy” the reader will assume it’s set here on Earth. With yours, all you need the reader to know is that at the start of the story, the world has been decimated by an inter-terrestrial war. Arguably, it’s not even essential at this stage to understand that they abandoned it – “In a world decimated by inter-terrestrial war…”. It could be believed the Earth won… makes for an interesting reveal when they find out it was actually abandoned. Makes it even more interesting if the protagonist is a war hero, a lynchpin to whole campaign, and with an ego to match. Pair him with a reluctant alien who reveals the truth at a crucial moment (All is Lost) and it suddenly feels more interesting.

Words like “audacious”… I don’t feel like they’re necessary. In every film, they start with one plan, which fails. Then they try something else, which also fails. Until they get to something so bonkers it just might work. EVERY winning plan in a film is audacious. That’s just how it works.

“Courageous” – he’s a lieutenant in the war… I feel like this is a bit of a given. Like saying a comedian is funny. Instead, as I mentioned before, give us something that tells us about his inner journey. Egotistical hints that is journey is a fall from grace. That he’ll realise he’s not as great as he thinks (and everyone else thinks). But he needs that to overcome the obstacles.

Which leads me to… antagonistic forces at work. Without knowing specifically what the plan is, we have no way of knowing how difficult it is and why it’ll sustain a 90mins+ runtime. A protagonist is only as good as the antagonist(ic forces) make them. John McClane is nothing without Hans Gruber. Harry Potter is nothing without Voldemort. Luke Skywalker – Darth Vader. It’s amazing how most of the iconic heroes have an equally iconic antagonist… Yours is slightly different, as we’re not dealing with a person, we’re dealing with a force. Something which makes this plan hard to execute I imagine. We need to know what that is.

“In a world decimated by inter-terrestrial war, an egotistical war hero must work with an alien POW and their advanced technology to XXXXX when the solar system is threatened by XXXXX.”

If the alien is an ally, it’s too easy. If you can add conflict, do it! Teaming the good guy with a bad guy is always popular and will do a lot to tell the reader about the relationship at the heart of this story. Two sides coming together to defeat a common enemy = winner!

I hope this helps. I’ve rambled a lot haha.