When the master of Porterhouse College, Cambridge dies of a Porterhouse blue, a stroke brought on by excessive living, having rejected all likely candidates to succeed him, the post passes to former Minister of Social Security Sir Godber Evans. This is not a popular choice with the staff, who are snobs, as former student Evans was a grammar school boy.

Despite his disdain for Zipser's studiousness Skullion does not report him but Zipser has another problem - he has the hots for Mrs. Biggs, his chubby, middle-aged cleaner. After a disastrous effort to get condoms in a pub vending machine Zipser goes to the suppliers and ends up with four gross of contraceptives by mistake.

Sensing his attraction, the bedder Mrs. Biggs creeps into Zipser's room for sex. She ignores his protests, but causes an explosion from the unknowingly blocked chimney. Sir Godber and Scullion clash over the consequences.

Cornelius Carrington comes to Porterhouse to make his film but it is an act of revenge for unhappy student days and he distorts the result to make the college seem like a salacious hotbed of sex. Skullion is interviewed live on his television show where he becomes a national hero for exposing the bribery and buying of degrees represented by his list.