Saw IV continues to answer questions about Jigsaw, even though Jigsaw himself is dead. It turns out one movie is not enough to tie up all the remaining loose ends, so actor Tobin Bell is still looking ahead to what Saw V and VI might reveal about Saw staples like Billy the puppet and the tricycle he rides.

"I can tell you that the tricycle that has appeared in all four Saw films has a very simple and human explanation to it which I hope that in V and VI we will both understand and have a window into," said Bell. "The origins of Billy, the meaning of that, I think you will see when you see IV that we've started to enter into that area. I think there is some marvelous storyline yet to be told."

Some skeptics might say, "Come on, you're going to explain the doll now? Do you have to explain everything?" Well, Saw fans want to know. "I think those two objects are simple things and everyone kind of has seen Billy since the beginning. Well, what is that? And why? Although perhaps you don't think about it, it has its effect on you. He has his effect and the tricycle has its effect when it enters the scene. I'm interested to show what those origins are. I think fans are really interested in known what the origins of very specific moments, especially Saw fans who are into the details. They just are. I'm always impressed with that."