Maurice R Hilleman saved more lives than any other scientist in the 20th Century. Given his extraordinary achievements, he is surprisingly little-known outside his field. He is the only scientist ever to make a flu vaccine in advance of a pandemic, a task scientists are now struggling to achieve in the face of bird flu. But, one of his creations, the combined MMR shot, remains controversial in the UK to this day. Jeryl Lynn Hilleman presents the incredible story of her father, Dr Maurice Hilleman.