The two strands—a survey of a community of quirky obsessives and a true-crime horror story—don’t quite mesh ... Frank’s painstaking research (he likens it to a kind of O.C.D.) yields evocative mini-portraits, whatever his subject ... This can become almost self-parodic ... But almost all such quibbles can be forgiven because of, well, the sheer depth of Frank’s skill. We can smell the damp wood and tequila in the Alaskan cabin where one Nazi-obsessed submariner builds his vessels, and we instantly admire the endlessly energetic Shanee Stopnitzky ... And Frank is right: It does make a difference to the reader to be able to picture Kim Wall’s last moments with loved ones. His book is a success if only for its ability to conjure so vividly Wall’s character and the tragedy of her death by someone who did not know her at all ... The one real misstep comes toward the end, as the diligent author, who seems to have spoken to everyone involved in Wall’s murder but the convicted killer himself, drives to a Danish prison for that climactic interview ... But then, standing in the parking lot, Frank aborts the mission. He never speaks to the central subject of his book.

Laden with detail and lyrical musings, Submersed sometimes groans under its own weight ... At times, Frank’s digressions get in the way of the larger story he’s trying to tell.

Scintillating ... The media turned Wall’s death into a sensation, but Frank’s thoughtful approach resists the temptation to revel in lurid details. Instead, he delves into the intriguing history of submarines and how the lack of personal submersible regulation results in catastrophes like the implosion of the Titan submersible near the Titanic wreck site ... Excellent for book groups, Frank’s unique approach is a distinguished tour de force.

A fascinating voyage among the hidden tides shaping a social niche ... A sharp researcher and stylish writer who’s 'obsessed with obsessives,' Frank sets aside his lifelong fear of the ocean in this excellent book to plumb the peculiar depths of the DIY sub community ... The story of the murder and its aftermath—including a prison sit-down between Frank and Madsen—provides a chilling throughline to an otherwise interdisciplinary look at what lies beneath the human compulsion to dive. Frank is witty and incisive...and he draws wonderful connections throughout.