4.48 Psychosis marks the ultimate narrowing of Sarah Kane's focus in her work. The struggle of the self to remain intact has moved from civil war, into the family, into the couple, into the individual, and finally into the theatre of psychosis: the mind itself.

This play was written in 1999, shortly before the playwright took her own life at the age of 28. On the page, the piece resembles a poem. No characters are named, and even their number is unspecified. It could be a journey through one person's mind, or an interview between a doctor and their patient.