Brenda (Tushingham) and Yvonne (Redgrave), two girls from the North of England, arrive in London to seek fame and fortune. However, their image of the city is quickly tarnished when they are robbed of their savings. Determined not to let her chance slip, Yvonne visits Carnaby Street in the hope of catching the eye of a trendy photographer, whilst Brenda has to stay behind and do the washing up in a 'greasy spoon' cafe after the girls can't afford to pay.
Yvonne does get spotted by a trendy photographer, Tom Wabe (Michael York), but for all the wrong reasons; she is singled out for being poorly dressed.
After several unsuccessful job attempts, Yvonne accidentally wins the star prize in a television game show and decides to invest the prize money in becoming a pop star. Her single, I'm So Young, though patently awful, becomes a big hit and she and Brenda drift apart. As Tom Wabe's muse, Brenda goes on to become a top model, while Yvonne's popularity wanes. However, at a glamorous party (at the top of the Post Office Tower) the girls realise the shallowness of the media business and decide to return home.