The Mystery Book Club choice is "Nine Lives," by Peter Swanson

Nine strangers receive a list with their names on it in the mail. Nothing else, just a list of names on a single sheet of paper. None of the nine people know or have ever met the others on the list. They dismiss it as junk mail, a fluke—until very, very bad things begin happening to people on the list.

FBI agent Jessica Winslow, who is on the list herself, is determined to find out. Could there be some dark secret that binds them all together? Or is this the work of a murderous madman? As the mysterious sender stalks these nine strangers, they find themselves constantly looking over their shoulders, wondering who will be crossed off next…