Inspired, in part, by accounts of abuse in psychiatric institutions, and by playwright Enda Walsh’s mother’s experience living with Alzheimer’s in a retirement home, Medicine is a darkly hilarious and deeply empathetic meditation on the way society deals with those deemed “mentally ill.” The play is set in a hospital, where John Kane is undergoing what appears to be drama therapy with two “attendants,” both named Mary, who replay traumatic episodes from John’s life both before and during his years-long institutionalization.