Marinette Dupain-Cheng was on her way to pursue her dream of becoming a heart surgeon, when all of a sudden: Zombie Outbreak Boat Party Massacre™
Marinette becomes a zombie. Because of this, she breaks things off with her social worker boyfriend, Adrien Agreste and becomes a recluse. She gives up becoming a heart surgeon and decides to work at the PD Morgue instead
Marinette’s roommate, Alya, is worried about Marinette’s reclusive habits
She’s terrified of someone finding out about her. But her boss, Nino, is quite eager when he finds out that his new resident is a zombie
Then a new detective joins the homicide division of the PD: Ali Prince.
So using the visions and skills from the brains of murder victims, Marinette teams up with Detective Ali to fight crime
On the other end, Chloé Bourgeois, the party girl who first turned Marinette, is strategically turning the wealthier citizens into zombies and selling brains at a high price.
Cue the whole CW drama thing with miscommunication, unnecessary drama, and terrible zombie reveals :)