Conversation so far:
What can you tell me about the films development?
The magazine's founder Bob Guccione wanted to produce an explicit adult film within a feature film narrative that had high production values.
What idea did he have in mind?
he decided to produce a film about the rise and fall of the Roman emperor Caligula.
Where was the movie developed?
The men's magazine Penthouse.
why was it developed there?
The magazine's founder Bob Guccione wanted to produce an explicit adult film.

Question: who was part of the movie development?
Self-contained rewrite: who was part of Caligula's development?