After a tragic accident leaves Scarlett comatose and with little chance of recovery, Tamsyn and Ed are out of options until a lifeline emerges in the form of an unusual medical trial. In exchange for the very best treatment for Scarlett, a fully furnished apartment, and a limitless spending account, the family must agree to move to Switzerland and welcome an artificial copy of their daughter into their home.

Suddenly their life is transformed. Tamsyn and Ed want for nothing, and the AI replacement, Sophie, makes it feel just like having their daughter back-except without all the bad parts. Sophie is engaged, happy, and actually wants to spend time with her parents.

But things take a turn for the worse when Scarlett makes a very real recovery and the family discovers that the forces behind their new life are darker than they ever could have imagined.