Background: Spontaneous hemorrhage from angiographically occult vascular malformations is not a rare occurrence. We present a case of in-hospital cavernous malformation rupture after initial normal CT. Methods: A 55-year-old female presented with severe headache with onset during activity, and normal neurological examination. Rapid neurological deterioration occurred 60 minutes following the CT scan. The patient was intubated, and repeat CT scan showed significant parafalcine ICH and intrahemispheric SAH. ICU transfer and expectant management led to neurological recovery and discharge to rehabilitation. Results: The patient underwent angiography on initial admission which was negative. A delayed MRI showed the presence of a cavernous malformation. This was followed conservatively with repeat imaging. The malformation remained stable. Conclusions: Our unique case highlights the sudden onset of hemorrhage occurring almost immediately following normal brain imaging. A cavernous malformation was discovered to be the cause, and was observed.