I call it like the domino theory of reality. If you can go one step at a time and it seems to make sense, you can then take your audience into an area that is relatively outlandish.

I remember when first, Stripes, and then Animal House came out - which I was really proud of, even though it was kind of loose and quite raucous - there were imitative movies that were not quite as good.

The home viewing experience is slightly different and there's room for these kinds of extra excursions.

My first student film was Orientation, which was basically the set-up for Animal House. There are a couple of scenes that we later borrowed in some form.

It's been about 15 years, and I've never really worked seriously in CGI and I thought that here was an opportunity to do the kinds of things that I was not able to do on Ghostbusters.

I always see things that I can improve. But frankly with Stripes, I'm surprised at how effective it is, even today, and how vibrant that movie is and how juicy the performances all are.

My sense is, I think it's okay for directors to do movies that speak to other work in their career.