"King Richard's Big Knight"

Well, this doesn't work, on a humor or character level, although there were little moments I liked, such as Marion stressing the importance of clean underwear, and the callbacks to previous episodes, like Richie almost dying on his own motorcycle.  So C.

A few notes:

• It's officially 1961 now.
• Gary Epp's middle HD role is as the Mickey-Finning Bullfrog.  
• And it looks like the boy who combs his crewcut in the old credits is the same guy who gargles when Fonzie and Richie enter the men's room.