Elizabeth Bellamy, spoiled and sanctimonious daughter of Sir Richard, moves back home after a drunken dalliance with a sly old fox (played by the inimitable Charles Grey) results in a pregnancy. Young Elizabeth was never a likable character, displaying all the traits of the selfish little upper class girl accustomed to having her backside kissed by daddy first then afterwards by one and all, but after her poisonous and insensitive treatment of her husband's bedroom difficulties, thankfully her days on the show were numbered.
Even though the writers chose to portray Elizabeth's infidelity and other personality defects sympathetically and as justifiable rather than morally deficient, she does get her just desserts in the end and eventually exits the show. The viewing public is rewarded for their patience with the infinitely more pleasant Georgina.
It's a shame British men have been treated as disposable servants of women, but it's unsurprising in the last days of a dying civilisation. It always seems to happen that way - once women are "emancipated" from whatever "oppression" they feel at the time it's only a matter of time before they consume their own society. It's amazing how the writers of Upstairs Downstairs were able to capture this detail so beautifully. It could not be done today, because all the female characters on British TV Drama these days must, by feminist decree, converge on a porn star cross between Andrea Dworkin and Sheryl Sandberg.
Well done Upstairs Downstairs, you've created a time capsule of immeasurable value.