The severe sequelae of infection from the conventionally termed 'benign' forms of malaria are being increasingly recognised, and delayed diagnosis and treatment lead to worse outcomes. The clinical picture can be non-specific and malaria epidemiology is constantly changing, presenting challenges for the acute clinician. The most critical step in the diagnosis of patients presenting in the UK is the clinician's awareness of the disease and its key presenting features. We describe a case of Plasmodium vivax malaria in a young man who presented with fever and diarrhoea, who had never travelled to a recognised malaria-endemic area. © 2013 Rila Publications Ltd.