We describe a 66-year-old female patient with no prior psychiatric history who presented with an unusual psychotic state, largely in accordance with Fregoli syndrome (misidentification of people). Further, the patient suffered from reduplication of time, scenic hallucinations and psychotic perceptions. Symptoms were the result of a brain metastasis originating from a lung carcinoma. We describe the performed (additional) diagnostics and discuss how to differentiate between organic and functional psychosis, as well as the given psychiatric treatment. Finally, potential pathophysiological explanations are discussed that might explain the (reduction of) symptoms in the patient.