Wit follows last hours of Dr Vivian Bearing, a university professor of English, who is dying of ovarian cancer. Over the course of the play, Bearing assesses her own life through the intricacies of the English language, especially the use of wit and the metaphysical poetry of John Donne. Vivian has spent most of her life preferring scholarship to humanity. She is unmarried and without children, her parents are deceased, and she has no third-party person to contact. Susie Monahan, a nurse at the medical centre, offers Vivian comfort. Vivian's only visitor, a Dr Ashford, reads to her from The Runaway Bunny, which she had bought for her great-grandson. Vivian then flatlines and walks from her hospital bed "toward a little light."