The Roof Leak - A Show Long Funny Rant About The Roof Leaking - Tremendous Improv Abilities
Channel: The Jayleno Fly
Date: 2017-05-30

I must have watched this episode about 15 times, It's a masterpiece!

I'm not a 100% sure it's improv, BUT, I know it's a little bit planned and if it's not improve, then Craig is amazing at faking improve. 

Craig Ferguson goes on a long rant about the roof of the tv-studio leaking, and hilarity ensues.