The Lightkeeper's Ball/Colleen Coble/ pp 288

"The Lightkeeper's Ball" takes place in 1910. Everyone is uneasy about passing through the tail of Halley's Comet. Olivia Stewart has even more immediate problems. After her father's death in a mining accident, Olivia's sister agreed to marry the son of their father's partner to insure their financial future. When her sister drowns accidentally, Olivia's mother wants her to take her sister's place. But Olivia suspects that her sister's death was no accident. When Olivia goes incognito as Lady Davenport to investigate her sister's fiance,Harrison, she survives an attempt on her life and finds evidence that her father may not be dead after all. Her heart tells her that Harrison is someone she can trust but everything points to him as her sister's murderer. This mystery has a surprising conclusion that I didn't see coming. This book is the third in the Mercy Falls series.