After reading DiMercurio’s ‘Emergency Deep’, I looked forward to the continuation of his new series with ‘Vertical Dive’. Finishing it, the book left me with mixed feelings. I liked the characterization, but I feel it was overdone. Although DiMercurio’s knowledge of submarine procedures is undeniable, the excessive detail and constant repetition during action sequences got to be distracting, impeding the flow of the story. I also found some of the plot elements somewhat unreal. Rachel is divorcing her husband Peter Vornado because he failed to tell her about his top secret CIA mission, while having an eye on his best friend Dillinger – and he doesn’t pick up clear hints she is interested in him, even while he is burying his wife of nine months. I expected more from DiMercurio.