Kathy
The main protagonist of the movie, Kathy is a 28-year old clone whose function is to be an organ donor. However, she manages to defer her fate by acting as carer to those who undergoing the operations and therefore takes the time to reflect on how her life could be different.
Tommy
One of Kathy's closest friends, and later, he love interest. However, Tommy is shown to be interested in Ruth. He and Ruth later break up but he does not see Kathy for the next few years as a result of his relationship with Ruth. When they reunite, they fall in love, but eventually, Tommy dies from his operations.
Ruth
One of Kathy's best friends. She is involved in a relationship with Tommy, but this leads to her eventually breaking ties with Kathy. She later reveals that she just did not want to be alone, hence the reason for her relationship with him. She dies from her injuries from the operation/donations.
Miss Emily
A teacher at Hailsham boarding school. She is honest about the purpose of the student's existence and reveals that they are to be organ donors. However, this leads her to be dismissed from her position.
Madame
Owner of an art gallery. The trip believe that if they prove love does exist between don donors this will allow them to be relieved from their organ donation purpose. However, she reveals this to be false, as clones do not have souls at all. She resigns them to their fate.