When Cassie Pengear's cousin Milly asks her to help a friend leave a blackmail payment at a party, Cassie's first impulse is to say no. That is until she realizes Milly will help no matter what she says, and when, not if, Milly gets in trouble, it will be up to her to get Milly out of it. But the payment doesn't quite go as planned, being interrupted by a dead body. And as Milly was involved in the payment, Cassie finds herself dragged into investigating the murder and the blackmail in the ballroom.