You would think that after decades in the entertainment business Robert De Niro wouldn't get nervous on a talk show. But he still does, he explained on The Late Show Wednesday night. Luckily, he had a very observant and accommodating Stephen Colbert as his host.

When De Niro joked, "I'm uncomfortable right here talking to you," Colbert made a deal with him. Thanks to a tip from Jennifer Lawrence, he knew the Oscar winner liked "extremely cold martinis," so he offered him a drink and to sit for a moment without exchanging any words.

"To silence," Colbert toasted. And that is just what they did, for a length of time that felt like an eternity (though it helped that both men made a few interesting faces). Watch Colbert and De Niro sit in silence in the above clip (towards the end) and in the video below.

Colbert then decided to take the opportunity to get acting tips from De Niro. But when the host read a line from a film called Three Santas ("This is two Santas too many!"), it turned into an elaborate explanation of the plot of the weird holiday movie, which Colbert said he was writing. "You're either attached to the project or you're not. In or off the bus, but the Santas are leaving the station," he told De Niro.

De Niro continued to question the plot until finally he said, "I need another drink." Watch De Niro give Colbert acting lessons here: