First of all, we’ve got two men among our survivors of the apocalypse, but only one woman. Second, one of those men is married to the woman, but we’ve seen reason to believe that she would honestly prefer to be with the other one at this point. Finally, the two men have also established that their philosophies of life are more or less mutually antithetical. What do you suppose all this might mean for the remainder of the film? You got it! it's a virtual non-stop three-way argument consuming nearly the whole of the remaining running time.