LONDON - In Ridley Scott's new sci-fi epic "Prometheus," the characters played by Michael Fassbender and Noomi Rapace have a peculiar relationship.
 
On one hand, both characters are pondering their origins.
 
Rapace's Elizabeth Shaw is leading an outer space mission with a goal that's no less than tracing the roots of humanity.
 
Fassbender's David is an android, so he has no roots, but he's fascinated by the people who made him, whether he's studying advanced linguistics or watching and rewatching "Lawrence of Arabia" to mimick the mannerisms of the young Peter O'Toole.
 
On the other hand, Shaw is a woman of cross-carrying faith, while David is a pragmatic rationalist, no more able to understand faith than several other challenging human emotions.
 
Head-butting ensues.
 
Off-screen, Rapace and Fassbender's relationship is humor-driven and the two volleyed one-liners back-and-forth both before and after I sat down with them last week at the London Film Museum in Covent Garden. If that humorous rapport doesn't always come through in this interview, that's probably because I was attempting to ask a few serious questions relatively early on the morning after the film's premiere.
 
Also check out my conversation with Charlize Theron & Guy Pearce and stay tuned for interviews with Logan Marshall-Green, Damon Lindelof and Ridley Scott in the days to come.
 
"Prometheus" opens on Friday, June 8.