Presumed dead, a vengeful old man uses his grandson as a vessel to help the police bust the cult that has destroyed his own life in order to save the human race.

Presumed dead, a vengeful old man uses his grandson as a vessel to help the police bust the cult that has destroyed his own life in order to save the human race.

So, let’s take things one at a time:

1. A cult wants to save the human race. – So far, so good.
2. In order to save the human race, the cult destroys the life of the Old Man. – Why? Who is this Old Man? Adolf Hitler? His whole existence (according to the cult) is against the salvation of the human race. Also: how do they do it? How do they destroy him? Be specific.
3. The old man wants revenge. – OK, so his life is not completely destroyed; they think he is dead, but he is not. That’s cool. We have a Monte Cristo situation and we want the protagonist to get his revenge and right the wrong, just like Kill Bill. (Or Monte Cristo.)
4. The old man uses his grandson as a vessel (for what?) to help the police bust the cult. – OK, this you have to explain more. What kind of vessel? For his spirit to live in? Is his body dead, but his spirit is alive? You have to be specific!

Also, I think I got confused by the word “vengeful,” which (at least for me) usually has a negative connotation and I initially thought that the Old Man is the villain of the story and its protagonist.

In Kill Bill, the protagonist is vengeful, but this is not the first adjective that I would put in the logline. You are probably looking for something along the lines of “a wronged old man…,” although I don’t even know if that’s a word…

Now, let’s get to the story. I will agree with Richiev, here; the story’s action feels very indirect:

1. he uses the grandson
2. the grandson helps the police
3. the police busts the cult.

Give the protagonist an action that he can perform directly. It will actually help you come up with a stronger concept.