Bill Watterson is often described as the Bigfoot of comic strips— a thing of legend, who is almost never seen or heard from, but is out there somewhere. So when Pearls Before Swine creator Bill Pastis reached out Watterson just out of the blue, he didn’t expect any sort of reply at all. What he really really really didn’t expect was that Bill Watterson would be a fan of Pearls Before Swine and that he would later take Pastis up on an incredible offer to collaborate on several Pearls comic strips. So if you’re a regular reader of Pearls Before Swine, you saw three days of Bill Watterson and probably didn’t even notice it. Or if you did notice the similarities to Watterson’s style, you probably thought that never in a million years that it could actually be him. But it was.