Lily James is ''fascinated'' by psychology and thinks her interest in the subject has helped her as an actress.

The 30-year-old star credits her life-long interest in the subject with benefiting her career because she is ''constantly trying to understand'' her characters and their way of thinking.

She told Psychologies: ''I am fascinated by psychology and philosophy. My father was a great thinker and he had a very analytic mind, as well as being spiritual.

''He always encouraged me to be curious and to discover things on my own and try to think matters through.

''I'm curious about human psychology and acting requires you to be constantly trying to understand your character's personality, thinking and motivations.''

Lily was just 18 when her father passed away and she wants to honour his memory by compiling a book of the stories he told her when she was younger, which she believed ignited her passion for acting.

She said: ''My father was my everything. He was my greatest inspiration and I loved listening to the stories he would create for children with incredible characters - like a cloud that talks and disappears when the sun comes out, and a cow that goes to the market.

''One day, I'm going to collect all his stories and have them published. He had an extraordinary imagination and helped me grow up in a world filled with joy and beautiful reams.

''I'm sure my interest in acting comes from my father and his stories.''

The 'Yesterday' star is also interested in singing, and has ''always'' had a passion for music.

She added: ''Ever since I was a child, I was always singing and dancing. Even today, whenever I'm cooking or relaxing in the house, I love to sing.

''Both my grandmother and my father were actors so I have it in my blood. I would love to play a singer.''