It is 1974 and the summer of love is drawing to a close. Kate Mularkey has accepted her place at the bottom of the secondary school social food chain. Then, to her amazement, Tully Hart - the girl all the boys want to know - moves in across the street and wants to be her best friend. Tully and Kate became inseparable and by summer's end they vow that their friendship will last forever.

For thirty years Tully and Kate buoy each other through life, weathering the storms of friendship, jealousy, anger, hurt and resentment. Tully follows her ambition to find fame and success. Kate knows that all she wants is to fall in love and have a family. What she doesn't know is how being a wife and a mother will change her.

They think they've survived it all until a single act of betrayal tears them apart. But when tragedy strikes, can the bonds of friendship survive? Or is it the one hurdle that even a lifelong friendship cannot overcome?