Long story short: Watchmen is set in an alternate 1985 where superheroes exist. The most powerful of them is Doctor Manhattan, a godlike superbeing accidentally created during a nuclear experiment gone wrong. His powers give the United States an advantage in the Cold War, and we take it, keeping the Soviet Union cowed. His powers have also left him detached from humanity, almost amoral.
The American advantage ends. Manhattan flees the Earth after being told that his powers have given those around him cancer. It turns out that this is part of a sweeping conspiracy involving the murder of superheroes which also has some unexplained connection to the resurgent Cold War. Manhattan also decides humanity is beneath his concern and he cares nothing for the fact that the world is tottering towards nuclear war.
Manhattan brings Laurie Juspeczyk (his former girlfriend) to Mars (it's not like he needs to breathe) to try to persuade him to help address the plot and save the Earth. He declines. Then he learns that Laurie's biological father was an important superhero murdered early in the film and...one who had unsuccessfully tried to assault her mother a few years before she was born. Laurie is horrified, but the Doctor takes a different view:
If you are unfamiliar with the book, the smiley face at the end is an ironic logo worn by Laurie's superhero father.
All of this brings me in a very, very roundabout and desperately geeky way to announce that today is our sixteenth wedding anniversary.
It is, quite truly, a miracle. As are our children. Any number of decisions--or indecisions--would have deflected us away from each other. And yet here we are. The same holds for you, dear reader, whether you are in a relationship or not. Your very existence is so unlikely that you should marvel at it from time to time.
I love you, Sweetheart. Here's to us, and our miracle.