She was 13 years old. Her father worked as a police officer and helped to infiltrate the Help Earth commune.
Later on, James goes to Joanna's house to use their phone to call for a taxi but he then goes upstairs to her room where they kiss and hug, until Joanna's father catches them and orders, Joanna, to go to bed and tells James to wait for the taxi outside. Joanna throws a paper aeroplane out her bedroom window, asking James to call her.
Joanna was slightly anarchic, with a cruel sense of humour.
She likes Thornton's handmade chocolates, rock music, blond-haired boys and her ambition was to ride a Harley Davidson across America.
In their brief romance, they kissed each other several times. They were fondly in love.
Her father was the village police officer. He was very strict and grounded Joanna because he did not approve of her going out with James.
She was very pretty. James described her as the 'best girl he ever met'. James was very upset when he had to leave her after his mission, as was Joanna.
After the mission, she was reported to have a new boyfriend, but James kept her paper aeroplane and photos of the tree where they first kissed.