Irish writer Sally Rooney, 27, turned heads last year with her clever debut novel Conversations With Friends, about a pair of young women in Dublin and their complicated relationships with an older couple - which did exactly what it said on the tin while somehow elevating it to literary heights.

Her bracing new novel, Normal People, which was longlisted for the Man Booker Prize, is a dark little millennial love story in which schoolmates Marianne and Connell begin a clandestine relationship.

"I don't know what's wrong with me," says Marianne, one of the protagonists. "I don't know why I can't be like normal people."

Connell's mother, a single parent, cleans for Marianne's wealthy family, a power imbalance that is reversed in school, where Connell hangs out with the popular kids and Marianne is an outcast.

They share a wordless knowledge that their relationship must be kept under wraps in small-town Sligo, Ireland, where the smallest rumour sparks vicious gossip.

When Connell inadvertently takes part in Marianne's social humiliation, this sets off a chain of events that reverberate throughout their lives, as they go to university in Dublin, navigate relationships with other people and yet keep gravitating back to each other.

Rooney has an unpretentious, matter-of-fact style that can be incredibly funny or ruthlessly lays bare what welters beneath the mask of the mundane - all without a hitch in tone.

She describes the intensity of Connell's feelings upon seeing Marianne while she is dating someone else: "She looked like a piece of religious art. It was so much more painful to look at her than anyone had warned him it would be, and he wanted to do something terrible, like set himself on fire or drive his car into a tree."

Rooney excels at finding words for the complex, commonplace emotions that people struggle to communicate to one another.

She also has her finger on the pulse of the moment: This story is inextricable from the contemporary concerns of the #MeToo movement and mental health.

Connell is literary, introverted and sinking into a depression he does not understand. Marianne has self-esteem issues so severe that it is wretched to witness how whole-heartedly she degrades herself.

She has internalised her trauma to a distressing degree: "Things that happened to her are buried in the earth of her body."

One ends up terribly invested in the painful love story of these two young people, so estranged from themselves. This is writing that takes apart normal people in the most extraordinary way. If you liked this, read: Almost Love by Louise O'Neill (Quercus, 2018, $29.95, Books Kinokuniya), another young Irish author with a gift for depicting difficult relationships. Sarah, a failed artist in her 20s, has an obsessive affair with a man twice her age, after which her life spirals out of control.