A friend of mine lent this to me a long time ago. I decided to read it as I have a bit of time right before school starts.
Planet Hulk starts with the Hulk being tricked by his "friends." They send him into space to a planet with no sentient life so that he will no longer be a danger to Earth. His shuttle accidentally goes through a portal and the Hulk finds himself on the planet Sakaar. The Hulk is enslaved by the Imperials and find himself a gladiator in their arena. Unfortunately for the Imperials, the Hulk allies himself with some of the other gladiators, and together the slaves fight not only for their own freedom, but for the very future of Sakaar.
I have to admit that Planet Hulk didn't really appeal to me when I first started reading it (or really at all - I didn't really want to read it, but I wanted to give it back to my friend). I found the beginning a bit slow and boring, which is rather odd as the Hulk has crashlanded on a planet and is turned into a gladiator. It was only about halfway through the story that I started to enjoy it. I thought it was entertaining, but I really have no desire to read the next part (World War Hulk). The end was a bit predictable in my opinion, and the whole thing just wasn't really for me.