"He’s unbelievable," the actor said when asked what it was like to work with Robert Downey Jr.
"He is so fast, funny and facile at playing in the moment. That is very, very special, and that’s exactly where I like to be."
As you'll probably already know, Shandling played a U.S. senator who wanted Tony Stark's Iron Man armour to be handed over to the US government for what he claimed was for the sake of national defense. When asked about his and Downey Jr's confrontation at that senate hearing, he revealed that he and the actor talked about how they'd do the scene before filming.
"I liked to improvise and he likes to improvise and Jon said that was fine as long as we gave him the story. So what was a five-page scene turned into a 15-page scene."
Iron Man 2 is out on DVD and blu-ray on September 28th in the US and on October 25th in the UK!