The story is about Justin Hitchcock, a professor of Arts and Architecture, who decided to overcome his fear of needles and donate his blood (it was also because he wanted a date with the pretty doctor) in Ireland. In another part of Ireland, Joyce Conway had a traumatic accident and had to have a blood transfusion. Since her accident, she finds that not only has her eating habits changed (from being a vegetarian to a non-vegetarian), but she can also speak Italian and Latin besides knowing a lot about old heritage buildings. She also has dreams of people and places which she doesn't know, although they all seem familiar to her in a way. At first, she thought she was going crazy because of the stress she's feeling, but after several incidents, she discovers that the changes are due to the blood transfusion - her blood donor was Justin Hitchcock, and that somehow, his eating habits, knowledge, interests and even memories have been passed to her.
I really like the story...there are many moments of sadness, but it also has its hilarious moments, not to mention many moral values. Cecelia Ahern is one the few authors who write using the present tense, which is probably why you feel as if you're really "in the moment" when reading. What's most intriguing, however, is the fact that there actually are cases of heart transplant patients who acquire their donor's skills, tastes, etc after the transplant. Although I'm not sure exactly if there are also similar cases involving blood transfusion. From the psychological perspective, more research could be done to find out if blood transfusions and heart transplants can influence the patient's behaviour and mental processes. Hmm...have to keep that in mind if I want to do a research someday.
So how does the story end?? Ooohh...the ending is just so, so sweet. Read it yourself!