Devlin's Light by Mariah Stewart

Criminal prosecutor India Devlin returns to historic Devlin's Light after her brother is murdered. So when her brother's good friend Nick Enright offers to help her investigation, India accepts. Soon a wonderful new emotion is glowing at Devlin's Light--a sweet, undeniable, very mutual attraction--and it's intensifying with each wave that crashes on the beach of the enchanting town by the bay.