Karen Wood, a New York bookseller, can’t keep it secret from her teenage son any longer. She has to tell him that he was conceived with the help of an anonymous sperm donation. He’s shocked and runs away.
Karen’s partner Daniel is also surprised. Karen is relieved when her mother, Rebecca, tells her that Luke is staying with her. While trying to reconcile with her angry son, Karen starts to look for Luke’s biological father.
Karen is looking forward to a new chapter in her life. Her boyfriend Daniel, a garden designer who creates little havens of nature on top of New York’s skyscrapers, has just moved in. Unfortunately her 13-year old son Luke is anything but excited about it. He’s at an age where he wants to know more about his father. Karen had told him his father was a Swedish exchange student.
When Karen tells him the truth after an ice hockey accident and Luke subsequently moves in with his grandmother, she decides to look for Luke’s biological father. But discovering the identity of the sperm donor is an almost impossible task as she finds more than one possible candidate.
Only when Daniel starts helping her with the research by pretending to be sperm donor number 108 at the placement agency, they find themselves on the right track. Unfortunately, it leads to a man who Karen deems utterly unsuitable as a father. But isn’t it Luke’s right to know about his roots? In the end Karen finds three fathers for Luke but only one of the men is Mr Right for her.