Downey was enthused to meet with Nolan, saying that any questions the director had about meeting at his home for a script reading would be answered with words beginning with “Y,” as in “yes.” Nolan invited Downey over to read “Oppenheimer” and to see if he might be interested in playing Strauss, and if he was previously familiar with the historical figure. Downey, as it so happens, was. He said:
“It has been a longtime contemplation, verging on obsession, of mine: mid-century Cold War and all the characters involved. I had a previous fair understanding of Strauss because I was fascinated with the mechanics of warfare, particularly in the Pacific theater in World War II. The first time I saw his name in print was regarding the proximity fuze and its development.”
A proximity fuze is a sensor used in bomb-making that can tell when a payload is close enough to its target to explode and do actual damage. Proximity fuzes were first used in bombs during World War II.
Downey’s immediate take on the script was that Strauss and Oppenheimer were close colleagues with something of an antagonistic mentor/prodigy relationship similar to the one seen in another notable Hollywood biopic from 1984, namely Miloš Forman’s “Amadeus.” This, he said, was a take Nolan didn’t expect. In Downey’s words:
“I challenged a little bit the Mozart-Salieri of it all. I said, ‘I’m not sure in some ways that Strauss isn’t a bit the hero here,’ which kind of raised an eyebrow on Chris. I half-jokingly challenged him on whether Admiral Strauss hadn’t done everything that any patriotic American would’ve done. And he said, ‘Well, this will be a wonderful ongoing dialogue. So, will you do the film?’ And he’s Chris Nolan, so he’s not asking your fricking agent.”