Digital Spy presents a picture preview of an explosive Grey's Anatomy two-parter to air on Five this Easter Sunday at 8pm.

The two-hour special, formed of two parts titled "It's the End of the World" and "(As We Know It)", tests the entire staff of Seattle Grace Hospital when an unexploded shell turns up in a patient being cared for by a new-on-the-job paramedic. A "code black" is declared, the hospital is closed and evacuated, and each and every member of the team is forced to confront their fears.

Izzie and George look on as the chaos unfolds

Meredith and Cristina peer into an evacuated OR