?Liam Santos comes to town to become a great artist, there he meets and falls in love with Fabio Grun, a successful young lawyer.? A car accident leaves the couple in a coma, only one of them can live thanks to the heart of one of them and thus be able to fulfill their dreams. —

Please take a look at the "Formula" link at the top of the page. A logline should be written from the viewpoint of the main character. As concisely as possible, it should tell us something about the MC, the inciting incident that kickstarts the story, and the MC's objective given the inciting incident. None of your suggested loglines gives us the information needed to evaluate the story.

I think that in your case, the MC is the one who survives, so write the logline from the viewpoint of the survivor. Mike Pedley has suggested is may be someone else altogether, if so write the logline from the POV of that person.

Remember, a logline is not a tagline. Taglines are designed to attract audiences. That is where you use flowery phrases like "A fatal accident tries to separate a love without limits". A logline should be more objective.

We don't need names in a logline or any of the back story.

Who's the actual protagonist here? From what I can tell, both your leads end up in a coma within the first act. That suggests to me that this story is actually about someone else who has to make the decision about which of these two should live and which should give his heart to the other. I really love that dilemma by the way, but their goal to "fulfil their dreams" is completely out of the control of either of these two characters. What's going to be happening on screen while these two are in a coma? I feel like this logline is merely a summary of act I making way for the actual protagonist of the movie to step forward at the break.

Consider doing this from the perspective of the person in charge of making that decision, or the doctor in charge of getting the families to make that decision - however you see it working. One person must be at the centre of this dilemma and his story is the most interesting in my opinion.

Definitely keep playing with this idea. Hope this helps.

An interesting idea, but the concept needs a bit more work. A car accident might leave a person brain dead and make them an organ donor candidate, but a car accident is very unlikely to leave a person with a damaged heart that requires replacement. Also, any donor heart would go to the person at the top of the waiting list, not the person in the next room.

What might make sense is if one of the couple has heart disease and is on a waiting list for a new heart. Then, you could have a situation in which the healthy person dies in an accident, and their heart is transplanted into their sick lover's chest. (It's still a stretch as there are donor compatibility issues, but the audience is likely to overlook that if you play it right.)

As for the mechanics of loglines, replace proper names by character attributes, don't give away the ending and keep the whole thing under 40 words (25 if possible).