reginald tate, who had played the title role in "the quatermass experiment", collapsed and died on 23 august 1955, aged 58. this was less than a month before the shooting of the location filming for "quatermass ii" began, and necessitated the casting of a replacement lead actor at short notice; john robinson was chosen to fill the part. robinson was an experienced actor from a range of different films and television programmes since the 1930s, but was uncomfortable about taking over from tate, and had difficulty in learning some of the technical dialogue he was required to deliver. robinson's delivery of his lines has been criticised by some later reviewers.