Rationale: Situs inversus totalis, vitamin B12 and D deficiency have been individually described to be associated with schizophrenia. This case is a patient, who had situs inversus totalis, showing psychotic features after a psychosocial stressor, together with underlying vitamin B12 and D deficiency. Patient concerns: A 22-year-old gentleman was admitted in a psychiatric hospital for further assessment of altered behavior in the form of receiving message from God to clean the earth and to save human beings. Diagnoses: Incidental finding of dextrocardia on electrocardiogram and chest radiograph. Ultrasound abdomen revealed situs inversus totalis. He had a low level of vitamin D and B12, 9 ng/ml and 136 pmol/l respectively. Brain computed tomography was unremarkable. Urine for illicit drugs was negative for amphetamines, cannabis, cocaine, and opiate. Whole genome array CGH (180k) did not identify any DNA copy number changes of known clinical significance. Interventions: He was treated with risperidone 2 mg tablet daily and vitamin D2 50,000 tablet weekly. Outcomes: His sleep and appetite improved, however, he remained withdrawn, anxious and in low mood. He travelled back to his home country on his fifth day of hospitalization. Lessons: Situs inversus totalis and schizophrenia is rare. In this particular case, vitamins B12 and D deficiency may have precipitated the onset of psychotic features in this otherwise healthy young gentleman.