Chuck is in Best in Show!
I am not a huge movie buff, so I mainly know Chuck (Michael McKean) from Better Call Saul.
But we were watching an old family favorite Best in Show last night, and there's Chuck, and he's GAY!
If you liked that, I highly recommend Christopher Guest's other mockumentaries:
This Is Spinal Tap (1984)
Waiting for Guffman (1996)
A Mighty Wind (2003)
McKean is also in the first and third, but don't sleep on Guffman as it is by far my favorite.