An immortal alien race must come out of hiding on earth and reunite, when an ancient enemy threatens humanity.

Highlander?

Just for fun, practiced loglining on an upcoming film. Using IMDB, converted taglines into a single logline by reducing character to type, and emphasising inciting incident plus goal (garnished with some story stakes).

@giannisggeorgiou - honorable samurai. Yes, "Examples" category, because, well, while I haven't seen the film, nor has anyone else really (except perhaps producer/director), the movie does however exists, with the release date of 'The Eternals' (2021) now reschedule to February.

Apologies @Andres_ . Yes, genre is technically Sci-Fi / Fantasy. Unfortunately forum system only supports one tag system.

Ok! Saving the best question til last. Thank you @Richiev , excellent point. And might be answered with the question "Who is the protagonist in 'Avengers: Endgame' (2019)?"
(Please note Avengers: Endgame (2019) forms backstory to The Eternals (2021))
The Antagonist is very clear (answer = Thanos), but the protagonist here is a team, collectively grouped by a common goal.

What's fun about playing with future release loglines is the potential to, well, change them. Feel I could have, but largely stayed true to pre-release marketing details.

I see this is posted under the "Examples" category. Is it an existing movie, then? Which one?