Focused Intensive Care Echo (FICE) is recommended in critically unwell patients to assess haemodynamic status and aid decision making. In certain circumstances, FICE can also be used as a diagnostic tool. We present a case where FICE identified a large left atrial mass in an intensive care patient with acute hypoxia and thromboembolic sequelae. This case demonstrates the importance of FICE in aiding diagnosis in complex patients where initial investigations are non-diagnostic. FICE is an essential skill for critical care physicians, and bedside echocardiography should be a standard investigation for all critical care patients.