Camera not rendering objects

I’m trying to render a 30 frame segment of my animation, but my camera has decided to not render anything other than blue sky. I’ve deleted all of my other cameras, and moved all pertinent objects to the same layer. Having done this it renders my background objects, but still omits my figure. I’ve checked the materials to make sure the alpha is one and that it receives light and all that.

I’m trying to use the quictime animation codec, and the other three minutes of cartoon that I’ve rendered has come out fine.

If it would help to post the blend file, I will glady, I’ll just need instructions on how to accomplish that.

Edit:
Never mind, at some point it decided that it was only going to render one layer. SO I move everything to that layer and voila, magically it works. But, the question remains, what cause es that, this tendency to render only the single layer?