Battle: Los Angeles is a war movie first, science fiction second. It's got it all: a burned-out retiring sergeant who gets drawn back in because, dammit, the Marines need him; the guy who's about to get married; the guy who's still a virgin; the guy suffering from shell shock and who just might crack; the newbie officer with a lot of book learning who you just know is going to freeze under pressure and have to be shepherded by that burned-out sergeant, who learned his lessons on the battlefield