"There were two serials in the 1940s."
Joel: Meanwhile at Stately Wayne Manor
Mike Biggs and Carl McMillan argue in front of Molly Flynn who is Batman and who is Robin while the three of them are eating lunch at the restaurant
Batman is seen in his own skit.
One of the trick or treaters is dressed up as Robin.
One of the boys on the street wears Sister Monica Joan's lost veil to play Batman.
Jase Robinson mentions the main character, Batman, in this movie
Xander mentions the main character, Batman, in this movie
Clips are shown (though Roger Ebert misidentifies it as the 1949 Batman serial).
Henry watches this show on TV