The sketch is introduced by a group of Gumbies (on film) who keep shouting "The Architects Sketch" over and over again until Mr. Tid (Graham Chapman) yells at them to shut up. They then start shouting "Sorry!" over and over, and Mr. Tid throws a bucket of water on them from several stories up.
The sketch proper begins with Tid in an office with two City gents (Michael Palin and Terry Jones). On a table near the window stand two architectural models of tower blocks. Mr. Tid informs the City gents that he has invited the architects responsible to explain the advantages of their respective designs.
First to arrive is Mr. Wiggin (John Cleese), who proceeds to describe his design's neo-Georgian features and modern construction, and then explains that tenants entering the block will be carried on a conveyor belt towards a soundproofed section containing rotating knives. Mention of knives alarms the first city gent. It turns out that Mr. Wiggin mainly designs slaughterhouses and has misunderstood the owners' attitude to their tenants. When Mr. Wiggin fails to persuade them to accept his design ("You wouldn't regret this—think of the tourist trade!") he launches into a long, impassioned tirade against "non-creative garbage" and blackballing Freemasons. When they still reject his design, however, he immediately recants and begs—unsuccessfully—to be accepted as a Mason because "Masonry opens doors."
Once Wiggin has been persuaded to leave, the second architect, Mr. Leavey (Eric Idle), arrives. Mr. Leavey proceeds to describe the strong construction and safety features of his design. His model promptly collapses and catches fire, in the manner of the recent Ronan Point disaster, accompanied by a large on-screen caption reading "SATIRE". The City gents assure Mr. Leavey that provided the tenants are "of light build and relatively sedentary" there should be no need to make expensive changes to the design. After his design is accepted, the model explodes.
This leads into a filmed section about "How to Recognise a Mason", in which Masons are shown engaging in such bizarre behavior as hopping down the street with their trousers around their ankles. Finally, there follows an animation in which an announcer attempts to "cure" a Mason (an animated cutout of Chapman) through behavioral therapy, in which he is rewarded for the correct response with a picture of a nude woman. The announcer asks the subject if he would like to give up being a Mason, showing him the nude picture several times as encouragement. When the Mason says "No", the enraged announcer crushes him with a giant hammer.