You're Wading Knee Deep And Going In, And You May Never Come Back Again.
... it's complicated. There have actually been around five or six Swamp Things -- those are just the main two. It's also not to be mixed up with Marvel Comics' Man-Thing, which is a remarkably similar character. Swamp Thing is a shambling plant creature that fights bad guys and tries to find a cure for his strange existence. He's a hideous thing who has super strength, can regenerate, and... um... control plants. It's cooler than it sounds, though not much cooler.
There have actually been some pretty good runs of the comic, the aforementioned Alan Moore one being the best. Of course, we know how pitiful Hollywood has been at adapting his works (The League of Extraordinary Gentlemen, V For Vendetta, Watchmen -- YES, I said Watchmen), so they've got a tough row to hoe.
Oh, and Joel Silver wants to make the film in 3-D. Of course he does. Because nothing says "action packed" like friggin' plants in 3-D.
You know what? I've let it percolate a bit, and I've decided -- this is a terrible idea.
However, it does give me the opportunity to show you this.
Wes Craven. The man has some serious misses on his resume, y'all.