Production was limited to thirty days, because the financing ran out.
The credit card that Luther Fox uses, to pay for taking Jennifer Adler out, was Director George Hickenlooper's own debit card. You can read his name on-screen (he has since cancelled the card).
Jason Robards almost took the James Coburn part. The producers also looked at Peter O'Toole, Nigel Hawthorne, and Jeremy Irons.
The Elysian Fields (or "Elysium") is the fabled place where ancient Greek heroes go to their final rest.