Colbert is finally known!

Stephen Colbert's second-to-last "Late Show" featured one cameo after another, including Robert De Niro, Ben Stiller and even Colbert's wife.

The celebrity guests asked Colbert questions ranging from his "favorite action movie" to whether he preferred "cats or dogs" ...

Stephen Colbert has spent many years challenging guests to his "Colbert Questionert", a series of rapid-fire questions that he claims allows the guest to be "truly known". And now, with The Late Show ...

Stars including Robert De Niro, Billy Crystal, Martha Stewart, and more quizzed the talk show host.

Stephen Colbert poses with his celebrity friends on the penultimate episode of 'The Late Show.' However, instead of Colbert asking the questions this time, the celebrity guests each took turns asking ...

Add Yahoo as a preferred source to see more of our stories on Google. Stephen Colbert poses with his celebrity friends on the penultimate episode of 'The Late Show.' Stephen Colbert's celebrity ...