This month, the Mystery Book Club meets to discuss The Cage, by Bonnie Kistler.  From the publisher:
 
On a cold, misty Sunday night, two women are alone in the offices of fashion conglomerate Claudine de Martineau International. Leaving at the same time, the two women, each preoccupied by her own thoughts, enter the elevator that will take them down from the 30th floor. When they arrive at the lobby, one of the women is dead. Was it murder or suicide? An incredibly original novel that turns the office thriller on its head, The Cage is a wild ride that begins with a bang and picks up speed as it races to its dramatic end.