Donny Franks – a.k.a. Stephen Colbert – spends the day as a Wrigley hot dog vendor

CHICAGO -- Hot dog!  Get yer hot dog here!  Wait a sec... is that?

Yes.  It's Stephen Colbert.

The Late Show host and die hard Cubs fan was at Wrigley Field Saturday slinging dogs and throwing out the first pitch.

But, he was in "disguise."

By the looks and sounds of it, he's filming a segment for the Late Show.

The Cubs are no stranger to Colbert and his show.

You may recall earlier this season when Colbert tried to bring the Cubs good luck.