himself. christo. >> looking ahead to monday, we return to fukushima, the never-ending nuclear nightmare. they are struggling to retain the disaster. we start the 4-part series. >> in the depths of japan's nuclear crisis, when each day's news predicts a darker day ahead, a small band of workers offered a ray of life. in a show of bravery employees faced daily doses of deadly radiation to bring the plant under control. they were known as the fukushima 50. >> translation: the so-called fukushima 50 was a group of those who stayed behind during fukushima's darkest hour. >> in a care interview we spoke with a nuclear engineer, one of the few who