Tangled Web by Wendy Saunders.
Cassandra Grayson leads a quiet life managing a library in Queens, NY. There’s only one thing missing… her sister.
Cassandra hasn’t seen her sister since the night their wealthy, prominent father died from a massive heart attack. She had only been five years old at the time and can barely recall the events of that night. All she can remember was that men came to the house and that it was the last time she saw her sister. Her alcoholic, emotionally unstable mother refuses to discuss her and will only say that she had been sent away to an exclusive boarding school in Europe. But, as the years pass by with no word from her, Cassandra begins to suspect there is more to her father’s death and her sister’s disappearance than she first thought.
Desperate to find answers she hires a private investigator, but when he turns up dead it becomes clear someone doesn’t want her looking into her family’s past. When wealthy businessman Jackson Evans stumbles into her life, with problems of his own, they realize his family and hers are inexplicably entwined in a web of deceit and murder, which spans two decades.
One by one, everyone who was in her home the night of her father’s death, begins to die under suspicious circumstances and it becomes a race against time to uncover the truth, before she becomes the next victim.