The dying master of Porterhouse, a fictional Cambridge college, succumbs to a Porterhouse Blue - a stroke brought on by over indulgence. He is replaced by Sir Godber Evans (Ian Richardson), who at the annual Founder's Feast announces great changes to over six centuries of tradition - egged on by his zealous wife, much to the concern of Skullion (David Jason) the head porter, and the Fellows.
In an attempt to prevent the radical changes, such as contaceptive machines, women students, and a canteen, a counter attack is planned by the Fellows and Skullion. He finds a reserve ally in old Porterhusian, Sir Cathcart D'Eath (Charles Gray). Meanwhile, Zipser (John Sessions) seeks confidential counselling with the Chaplain (Lockwood West) on his fixation for Mrs Biggs, the buxom bedder (Paula Jacobs).