Godplayer. Robin Cook. 1983.

It starts as a marriage of true minds - two gifted young physicians burning with the will to heal, soulmates as well as lovers. From the moment that Cassandra Cassidy meets brilliant cardiac surgeon Thomas Kingsley she knows they are meant to be together. Forced by a deteriorating eye condition to switch from her chosen field of pathology to psychiatry, Cassandra needs the support and approval of the charismatic doctor and Thomas, privileged only child of a banker-industrialist, finds in the beautiful and vulnerable girl the devotion he desperately desires.

But as Thomas continues his meteoric rise, Cassandras marriage begins to disintegrate. Saintly to an admiring public, Thomas is something else to the woman who loves him - an erratic and hostile stranger whose inexplicable rages become more frequent. 

Then the dependable security of the hospital world around her becomes increasingly menacing: Cassandra is convinced that someone is killing terminally patients - someone who holds the power of life and death in his hands.

Against her husband’s furious objections, Cassandra takes it upon herself to stop the killings even as she fights to save her marriage. Only after she stumbles onto a terrifying discovery is she forced to realise that her dreams have metamorphosed not nightmares and that her search for the truth has opened the floodgates of horror.