Plain Peril by Alison Stone

After her sister is found dead and her brother–in–law goes missing, Hannah Wittmer rushes back to the Amish community she abandoned to care for her young nieces. Although she makes every effort to blend in, she's still seen as an outsider–and quickly attracts the attention of a killer.

She knows Sheriff Spencer Maxwell is fast on the murderer's tracks, but the Amish townspeople are as suspicious of him as they are of Hannah. As threats escalate–now targeting Hannah and the handsome sheriff–they'll follow any trail to uncover a vicious criminal. Even if that trail leads them right to their own backyard…