Speaking of roles in the movie, Kubrick said in an interview that the casting plan had Peter Sellers playing a fourth part, that of Maj. "King" Kong. But Sellers couldn't climb around in the bomb bay due to a leg injury, so they hired Slim Pickens, which turned out to be even better. Kubrick also said that the original concept was a straight drama, like "Fail-Safe", but he found that "we were being forced to throw away a lot of good stuff because it was too hilarious, so we realized that the movie would have to be a comedy."