Basically, after turning into vampires Stefan and Damon escape to New Orleans. *spoilers* Damon somehow ends up in a freak show circus in a death match with a lion. Stefan "tries" to find a way to rescue him, something he is making a lot harder than it actually is (he has vampire strength and speed, but he just stands there with Damon practically a touch away) while falling in love with the ringleader's human daughter, who seems to change personalities somewhat often. He ends up getting caught (of course) and Damon and Stefan end up in a match with each other. Predictably, Callie rescues them because of that whole "yay, true love" bit, and Damon ends up killing her. It ends with Stefan saying he'll never love a human girl again, which we all know is a lie. 
 If you couldn't tell, I wasn't much of a fan of this one but I'll probably torture myself with reading the next one.