Heather O'Neill is a Canadian novelist, poet, short story writer, screenwriter, and journalist. She was born in 1973 in Montreal and attended McGill University. O'Neill published her debut novel, Lullabies for Little Criminals, in 2006. The novel was a significant success, being selected for the 2007 edition of Canada Reads, where it was championed by singer-songwriter John K. Samson and won the competition.

The book also won the Hugh MacLennan Prize for Fiction and was shortlisted for eight other major awards, including the Orange Prize for Fiction and the Governor General's Award, and was longlisted for the International Dublin Literary Award. It became an international bestseller and established O'Neill as an influential figure, recognized by Chatelaine as one of the most influential women in Canada.

Following her debut success, O'Neill continued to write compelling works. Her books The Girl Who Was Saturday Night (2014) and Daydreams of Angels (2015) were both shortlisted for the Giller Prize. Her third novel, The Lonely Hearts Hotel, was published in February 2017. O'Neill's diverse talent also includes contributions to screenwriting, poetry, and articles for prestigious outlets like The New York Times Magazine and This American Life.