At 1:23 a.m. on April 26, 1986, Reactor No. 4 at the Chernobyl Nuclear Power Plant near Pripyat, Ukraine, suddenly exploded. In the bleak darkness of night, large amounts of radioactive material entered the atmosphere and spread across the Soviet Union and Eastern Europe. Firefighters arrived at the scene immediately, but lacking effective protective equipment, they suffered irreversible and devastating injuries.