Look, up in the sky! Is it a bird? Is it a plane? No, it's !El Sancho!
It sounds great doesn't it? One might actually believe El Sancho is a superhero. Sadly, he's far from it.
If you're a guy and your wife is cheating on you, the other man is called "El Sancho".
This is very a common phrase in Mexico, let's hope this is something you never have to worry about.