A Silence of Angels — Mark Teppo

After years of estrangement, Salvatora Quagmire receives an enigmatic phone call from her father. She comes home and finds no one running the office at Quagmire Investigations. While looking into the disappearance of her father, Sal is asked to investigate the death of Harvey Cartwright, a local engineer who knew her grandfather, the man who founded the family agency.

Aided by a hacker who sees patterns everywhere and an up-and-coming detective on the local police force, Sal starts to unravel a mystery involving lost cosmonauts, Civil War-era pistols, and renegade spiritualists. And when the enigmatic Night Office shows up, Sal has to confront the secret she's been hiding for many years.

Sal, you see, can talk to ghosts . . .