on that first night -- warm , muggy aug. 9 , 1969 -- manson followers susan atkins , 21 ; patricia krenwinkel , 21 , and charles -lrb- tex -rrb- watson , 23 , invaded the benedict canyon home leased by tate and her husband , film director roman polanski , and killed the 27-year-old actress , who was 8 1/2 months pregnant .