Why William Shatner can't say 'no' (Part 1 of a 2-part interview)

At the age of 80, William Shatner is still going at "warp speed." That's right - Shatner is 80!

He's an award-winning television actor, commercial pitchman and spoken-word artist. And his new book reveals how he did it.

It's called "Shatner Rules: Your guide to understanding the Shatner-verse and the world at large."

CNN's Ali Velshi sat down with Shatner and asked him about critics who say Shatner won't turn anything down.