Writers! If i gave you a brainstorm with "survival at all costs" in the middle what would you...?

"Survival at all costs" would tell me that some difficult decisions have to be made, so it couldn't be as simple as good guy vs bad guy, it would be like, 'we're on an island, there's 10 of us, but only enough food for 5 people to eat until we get rescued' so it would be fighting friends, or simply innocent people against innocent people. Good people will have to do bad things in order to live through it, so for the character it becomes an issue of "I have to so this to live, but can I live with myself if I do this"