I wish people would spend the time and put a little effort into actually explaining the story line of a film properly but, I can't see that happening with the deterioration of common sense so rampant in the world today! 😠
The film is an Apocalyptic one but, its not about 3 groups of people making an alliance in order to cross an apocalyptic landscape filled with danger. Its a film of 3 short stories of individual pairs in their own stories yet all within the same pandemic timeline. Its also Sci-Fi in plot description only (there are no space ships such as that are on the ad posters) and their are absolutely no Zombies whatsoever.
The first story began well and continued to grow and had a little suspense and tension to it but, it flat-lined a little just before its conclusion;even though the main character of it was very good/convincing. The second story never really got going at all and had it done so, it would have needed an entire film of its own to tell the tale properly.
The third tale wasn't worth its inclusion - IMHO - as its script was extremely poor and two of the characters I was just hoping would shoot each other and end it...before I did! 😁
However having said my piece, I found them just making the grade of interesting enough to watch (but only ever once) and only if you have absolutely nothing else.