F. Cottam - Dark Echo

Dark Echo Because this boat isn't just unlucky, it's evil. It was built for Henry Spalding, a soldier and sorcerer who committed suicide yet still casts his malevolent spell nearly a century after his death. Suzanne must uncover his last, terrible secret before 
 destroys the man she loves.
From Publishers Weekly
When businessman Magnus Stannard buys Dark Echo, a haunted yacht, at the start of Cottam's overstuffed occult thriller, it fulfills a dream from his impoverished childhood: to own the luxury boat he saw in one of his favorite books. But Dark Echo's American builder, WWI hero Harry Spalding, had an unsavory history of evil exploits, and everyone who's owned the ship since his suicide has suffered misfortune and a grim death. Magnus and his son, Martin, become the latest victims of the yacht's malignant legacy when, after setting out in it to cross the Atlantic, the ship reveals the malevolent mission it has chosen them to complete. Cottam (The House of Lost Souls) works up a byzantine backstory for his spook ship that's imaginatively complex, but that thwarts thrills with its confusing historical detail, digressions into Martin and Magnus's relationship, and shifts of narrative viewpoint. What could have been an exceptional tale of maritime terrors reads more like a horror story adrift at sea. 
From Booklist
Can a haunted object continue to cast the spell created by its evil, long-dead creator? That may be the case of Dark Echo, the oceangoing yacht in this religious-suspense/horror blend spanning the better part of a decade. Cottam sets the scene with a stunning description of nonhuman malevolence embodied in the fog covering 1917 Rouen. Add five deeply buried corpses forming a five-pointed star, a pentagram used in rituals involving animal sacrifice, and a priceless and missing holy relic thought to have delivered the final death blow to the crucified Christ, and this is one compelling story. Along the way, readers will enjoy uncovering the secrets of the regatta-winning racing schooner and its owner, the dashing millionaire Harry Spalding, as Suzanne, a contemporary heroine with a knack for research and the determination to save the man she loves, delves deep and discovers a box filled with 80 years of darkness. A shivery and entertaining read for the beach or firelit evenings.