Lisa Duffin - known to all as Duffy - joined the ED as a newly qualified nurse. She was carefree, with an interest in astrology, yo-yo diets, gossiping and trying to pass her driving test. But she was always shown to be a tough, determined woman, arranging a demonstration against the closure of the nightshift. However her happy go lucky character changed when she was raped. She didn't go to the police - which she later regretted - instead confiding in Megan.
Duffy was promoted to Sister and fell pregnant by one of the doctors, Andrew. However, she realized she didn't love him and decided to raise the baby alone. Duffy did eventually marry Andrew and they decided to leave Holby when she became pregnant with her second child.