Paul Johnston 
The White Sea: A contemporary thriller set in Greece starring private investigator Alex Mavros [EPUB ebook] 

Alex Mavros enters a chilling world of power and corruption when he investigates the kidnapping of a wealthy Greek ship-owner
Wealthy ship-owner Kostas Gatsos has been missing for several weeks, having been snatched from his luxury villa on the idyllic island of Lesvos. Curiously, there has been no ransom demand. When the police investigation stalls, the desperate Gatsos family turn to private investigator Alex Mavros for help.
Inherently suspicious of the super-rich and initially reluctant to take on the case, Mavros finds himself dealing with a highly dysfunctional family with more than a few skeletons in its closet, a family whose tentacles have a surprisingly wide reach. Alex believes the key to the mystery lies in the ship-owner’s shady past and sinister business deals – but the truth behind the kidnapping is more disturbing, and closer to home, than Mavros could ever have imagined.