This is the only appearance of the Bunkers' cellar.
The uncredited voice on the tape recording of the heretofore talked about, but unseen, character Stretch Cunningham is performed by Billy Sands, who had occasionally played bit parts on the series. When an actual appearance by the character was required in a later season, however, he was played by lanky character actor James Cromwell - perhaps because no one would have nicknamed the diminutive Sands "Stretch."
One of the original concepts for inclusion in this season was to showcase Archie and Irene having an affair. However, it was decided that these two characters "getting together" would've been too absurd. While Archie and Irene are alone together, they actually bring up the subject, pointing out its absurdity.
Cousin Emily was previously referenced in the 1972 episode "Edith's Problem".