In this paper, I describe and discuss the complexities of being a therapist in a maximum security forensic psychiatric hospital, working with patients who have committed acts of serious violence, and who also suffer from severe mental illness and personality disorders. I suggest that profound disturbances in the patient's inner world get played out in triangular disputes between the patient, the therapist and other professionals working in the hospital. I also describe how real events in the life of the institution impact on the therapeutic process, and the importance for the therapist of reflection on the ‘other 23 hours’ that the patient lives outside of therapy. Finally, I raise some ethical dilemmas that arise for therapists working in such settings, where the stated therapeutic aim is not only treatment but also the containment and prevention of future violence.