This is the story of friendships that cohere at a northern university in the 70s. The narrator, Adele, was born and brought up in a Jewish family in Liverpool: "I grew up to be the leader of a circle of schoolgirls, bolshy, sophisticated, ambitious, supercilious, a little bit cynical already, who smoked and wore plum-coloured lipstick and very short skirts."
She has a terrible secret: her father, Harry, a petty criminal, killed himself when he was exposed as the organiser of a small Ponzi scheme. The family and their world are changed for ever. But, like her mother, Adele is a strong woman. She takes a job at the perfume counter of Lewis's in Liverpool. She quickly finds it stultifying, but is determined to do better and talks herself into one of the new universities in Yorkshire by pretending to be Allen Ginsberg's cousin.
At university she is soon involved with a new group of friends, and the novel revolves around their fates. It is an era when students believed that they could change the world; that false consciousness was a blight to be overcome; that people could elect to be gay or straight; that socialism, along the lines of Marcuse, would triumph; and that mental illness should be understood, as RD Laing prescribed, as an aspect of normality. On the campus there is a vogue, no doubt influenced by David and Angie Bowie, of dressing up to suggest that there are no absolutes of sexual orientation. Adele takes none of these notions seriously.
The centre of the story is Evie, who arrived at the university as Lorraine, but changed her name when she took up with Stevie, also known as Stephen Platt. They swap clothes, and in some ways became one androgynous person, but their relationship breaks down. Stevie leaves after a few terms – and dies on the night of Adele's 20th birthday.
"If you go back and look at your life there are certain scenes, acts, or maybe just incidents on which everything that follows seems to depend," muses Adele, many years later. "If only you could narrate them, then you might be understood. I mean the part of yourself that you don't know how to explain."
Linda Grant gives the impression of looking for an organising principle for the novel: the mystery of Evie's demise. For many years after they have all left university, Adele is obsessed by what happened on the fatal night. Who saw her last? Who could have helped? Who is to blame? But the problem with this otherwise fine novel is that there is not much of a mystery to be solved. Her family secrets, revealed in some handy notebooks, are not really very significant. Evie was a troubled child, ethereally beautiful, and caught up in something she didn't fully understand.
But Grant excels in capturing the absurdity of the times, and the phenomenon of a university consciously trying to introduce societal change through exposure to brutal architecture and experimental teaching. She is also brilliant on the naivety and vulnerability of the young students, from flamboyantly gay Bobby to Gillian, the viola player turned revolutionary. Rose, who becomes a successful barrister, acknowledges at the friends' final meeting that she was exactly the graduate the university was trying to produce: "My life has never departed from the plan. It all worked, didn't it? It worked terribly, terribly well."
You could read into this Grant's feeling that the higher banalities have come to roost and have not left us. "There was a revolution," says Adele, "just not the one they had in mind."
It is a great talent to be able to keep afloat so vividly and so plausibly this many characters. While not exactly a feelgood book, Upstairs at the Party has the great virtue of being a wonderfully and perceptively written story, which rings utterly true, and as a consequence lifts the spirits.
• Justin Cartwright's latest novel is Lion Heart (Bloomsbury). To order Upstairs at the Party for £11.99 with free UK p&p call Guardian book service on 0330 333 6846 or go to guardianbookshop.co.uk.