Katherine has everything under control. After years of struggling to conceive with her partner, Patrick, she finally gives birth to Rose, her IVF miracle child.

But she's afraid that Rose may not be her daughter, her pale skin not matching Katherine's own.

Tess never got her happy ending. Just like Katherine, she was also a hopeful IVF mother, but her daughter, Hanna, was stillborn.

Now divorced, broke and stuck in a dead-end job, she's beginning to lose all hope. But when Rose is ten months old, both women get a call from the fertility clinic. There was a mistake: their eggs were switched.

It will take a custody battle like no other to decide who will get to be Rose's mother - a battle that will push them both to the brink. This is a story about what it means to be a mother, and the lengths we go to for the people we love.