If there's one thing Robert Downey Jr. does best as Tony Stark, it's delivering his superhero lines as if he's making them up as he goes along.
But despite the actor's spontaneous, scenery-chewing demeanor, "Iron Man 3" co-star Sir Ben Kingsley said Downey is always working with his fellow actors, not against them.
"I think that as in any collaborative event, even if people are opposed to one another, like tennis players, you have to keep your eye on the other player," Kingsley told MTV News. "You have to anticipate and joy in the movements and twists and turns. Robert never strays off dialogue. His gift is to make the written word look utterly spontaneous."
Kingsley plays the Mandarin, a mysterious figure who aspires to destroy America's decadent Western values. A sort of "super-terrorist" created almost from the iconography of the worst leaders in history, Mandarin dons a bin Laden-like beard and extensive visual representations of his exoticism — his otherness.
The actor's responsibility was to remain placid, certain and resolute in his authority, a challenge he said was less difficult than one might expect when pitted against Downey's quick wit and febrile intelligence. "Very little if anything is thrown at the actor that isn't in the script," he said. "So we do have a map, and we can stick to the map.
"I think he calls it the box," Kingsley continued. "You play inside it, you don't play outside of it. So he's a very stimulating and wonderful comrade to work with."
Watch Kingsley and Downey share the screen in "Iron Man 3," which is in theaters now.
Check out everything we've got on "Iron Man 3."