Attending what they believe to be a farewell party, a group of friends discover the host has been diagnosed with an incurable disease and plans to take his own life at the end of the night, unless they can convince him not to.

I like the idea, because it creates a tense and interesting environment and could be shot within few locations. It's a feasible yet promising proposal.

As asked above, who is the protagonist: the suicidal host or one of the guests? For my 2.5 cents worth, I would consider making the suicidal host the protagonist. Richer, more complex, and deeper psychological material and issues to explore.

And as suggested, I would consider reframing the stakes by having him resolved to commit suicide for reasons other than he's doomed to die soon anyway. Perhaps the ostensible reason could be existential (philosophical despair: life is meaningless); or clinical depression; or because of impending financial ruin, bankruptcy; or because of an accident that has reduced a vibrant, active man (or woman) to an incontinent, impotent paraplegic.

Or all four.

As asked above, who is the protagonist: the suicidal host or one of the guests? For my 2.5 cents worth, I would consider making the suicidal host the protagonist. Richer, more complex, and deeper psychological material and issues to explore.

And as suggested, I would consider reframing the stakes by having him resolved to commit suicide for reasons other than he's doomed to die soon anyway. Perhaps the ostensible reason could be existential (philosophical despair: life is meaningless); or clinical depression; or because of impending financial ruin, bankruptcy; or because of an accident that has reduced a vibrant, active man (or woman) to an incontinent, impotent paraplegic.

Or all four.