O'Bannon and John Carpenter attended USC together; the result of their meeting
each other in college was the low-budget cult science-fiction parody
Dark Star (1974), which started out as a student movie and was eventually
expanded into a theatrical feature.
O'Bannon was reputed to suffer debilitating stress-induced stomach
aches (which some detractors attributed to hypochondria). Upon his
death, Diane O'Bannon revealed that her husband had been managing
Crohn's Disease for about thirty years.
Dan O'Bannon had been working on the screenplay for Screamers (1995) as early as 1981. The October 10, 1984, draft credits Michael Campus as co-writer. It is unknown whether Campus also intended to direct.
He was considered one of the most brilliant, if volcanic, alumni of the USC film school.