Sir: We believe that we have come across a new symptom of schizophrenia and would welcome comments. A 38-year-old male, with a history of schizophrenia, was admitted following a disturbance at a public house. Our only source of history was the landlady, who described increasingly bizarre behaviour over the preceding 4 weeks. After purchasing a pint of beer he would take two steps forwards, take a drink, move a step to the side, take another drink, then return to his start by completing the rectangle.

We have searched the literature, finding no evidence of such actions and therefore suggest this is the first description of ‘knight's move drinking’.